412 Sentences With "efferent" | Random Sentence Generator

Afferent is derived from Latin participle afferentem (af- = ad- : to + ferre : bear, carry), meaning carrying into. Ad and ex give an easy mnemonic device for remembering the relationship between afferent and efferent : afferent connection arrives and an efferent connection exits. Another mnemonic device used for remembering afferent and efferent (in terms of the spinal cord, with its dorsal/ventral organization) is SAME DAVE. Sensory Afferent Motor Efferent, Dorsal Afferent Ventral Efferent.

There are three types of efferent fibers: general somatic efferent fibers (GSE), general visceral efferent fibers (GVE) and special visceral efferent fibers (SVE). Subtypes of general somatic efferent fibers include: alpha motor neurons (α) – these target extrafusal muscle fibers, and gamma motor neurons (γ) that target intrafusal muscle fibers. Beta motor neurons target both types of muscle fiber and there are two types known as static and dynamic.

Afferent and efferent are connected to affect and effect through their common Latin roots: Afferent nerves affect the subject, whereas efferent nerves allow the subject to effect change.

The rest passes into an efferent arteriole. The diameter of the efferent arteriole is smaller than that of the afferent, and this difference increases the hydrostatic pressure in the glomerulus.

Both afferent and efferent come from French, evolved from Latin (the basis of many terms in medicine and biology) for the terms, respectively, ad ferens (Latin verb ferre: carry), meaning carrying into, and ex ferens, meaning carrying away (ad literally means to, and e = ex means from). Ad and ex give an easy mnemonic device for remembering the relationship between afferent and efferent: afferent connection arrives and an efferent connection exits. Afferent and efferent are connected to affect and effect through their common Latin roots: Afferent nerves affect the subject, whereas efferent nerves allow the subject to effect change.

In addition, the spindle also has a motor efferent innervation carried by the efferent nerve fibers of gamma motor neurons, which is used by the nervous system to modify the spindle's sensitivity.

Their efferent vessels pass to the superior deep cervical lymph nodes.

The postcava is well developed, formed by large efferent renal veins.

The oxygenated blood from the heart leads to the aorta, to sinuses where it oxygenates tissues. Deoxygenated blood goes to efferent branchial vessels in cerata. These efferent vessels can be seen in a transverse section of the cerata as widish canal to pass up the opposite margin. From efferent vessels the blood goes into afferent vessel, where is gets an oxygen.

The contralateral efferent limb causes consensual light reflex of the contralateral pupil.

The term general efferent fibers (GVE or visceral efferent or autonomic efferent) refers to the efferent neurons of the autonomic nervous system that provide motor innervation to smooth muscle, cardiac muscle, and glands (contrast with SVE fibers) through postganglionic varicosities. GVE fibers may be either sympathetic or parasympathetic. The cranial nerves containing GVE fibers include the oculomotor nerve (CN III), the facial nerve (CN VII), the glossopharyngeal nerve (CN IX) and the vagus nerve (CN X).Mehta, Samir et al. Step-Up: A High-Yield, Systems-Based Review for the USMLE Step 1.

The inflammatory reflex is a neural circuit that regulates the immune response to injury and invasion. All reflexes have an afferent and efferent arc. The Inflammatory reflex has a sensory, afferent arc, which is activated by cytokines, and a motor, or efferent arc, which transmits action potentials in the vagus nerve to suppress cytokine production. Increased signaling in the efferent arc inhibits inflammation and prevents organ damage.

The facial nerve also functions as the efferent limb of the corneal reflex.

Special visceral efferent fibers (SVE) are the efferent nerve fibers that provide motor innervation to the muscles of the pharyngeal arches in humans, and the branchial arches in fish. Some sources prefer the term "branchiomotor" or "branchial efferent". The only nerves containing SVE fibers are cranial nerves: the trigeminal nerve (V), the facial nerve (VII), the glossopharyngeal nerve (IX), the vagus nerve (X) and the accessory nerve (XI).Drake et al.

Therefore, these cells are the origin of the earliest efferent pathway of the developing cortex.

Additionally, vasopressin selectively contracts efferent arterioles probably through the V1R, but not the afferent arteriole.

The efferent arterioles are blood vessels that are part of the urinary tract of organisms. Efferent (from Latin ex + ferre) means "outgoing", in this case meaning carrying blood out away from the glomerulus. The efferent arterioles from a convergence of the capillaries of the glomerulus, and carry blood away from the glomerulus that has already been filtered. They play an important role in maintaining the glomerular filtration rate despite fluctuations in blood pressure.

This is in contrast to efferent lymphatic vessel which are also found in the thymus and spleen.

In the CNS, afferent and efferent projections can be from the perspective of any given brain region. That is, each brain region has its own unique set of afferent and efferent projections. In the context of a given brain region, afferents are arriving fibers while efferents are exiting fibers.

The pupillary light reflex neural pathway on each side has an afferent limb and two efferent limbs. The afferent limb has nerve fibers running within the optic nerve (CN II). Each efferent limb has nerve fibers running along the oculomotor nerve (CN III). The afferent limb carries sensory input.

Hess RA 2018. Efferent ductules: structure and function. Encyclopedia of Reproduction. Skinner MK. San Diego, Academic Press: Elsevier.

The synapse between the afferent and efferent limbs occurs in the lowest sacral segments of the spinal cord.

The afferent arterioles, then, enter Bowman's capsule and end in the glomerulus. From each glomerulus, the corresponding efferent arteriole arises and then exits the capsule near the point where the afferent arteriole enters. Distally, efferent arterioles branch out to form dense plexuses (i.e., capillary beds) around their adjacent renal tubules.

The distal portions of the postcardinal veins form the efferent renal branches and the ascending trunks of the postcava.

Kidneys of common ravens receive arterial and afferent venous blood and are drained by efferent veins. In terms of the arterial blood supply, the arteries entering the kidneys branch into numerous smaller arteries and eventually form afferent arterioles that supply the glomeruli. The peritubular blood supply is composed of efferent arterioles leaving the glomeruli of reptilian-type nephrons that drain into sinuses of the cortex. On the other hand, the vasa recta are formed by efferent arterioles exiting the glomeruli of mammalia-type nephrons.

You callow hollow of the efferent, the apsis-axis of my implement, ague body, unboundaried, portionless plot no chart remarks.

Like other neurons, lower motor neurons have both afferent (incoming) and efferent (outgoing) connections. Alpha motor neurons receive input from a number of sources, including upper motor neurons, sensory neurons, and interneurons. The primary output of α-MNs is to extrafusal muscle fibers. This afferent and efferent connectivity is required to achieve coordinated muscle activity.

Efferent nerve fibers refer to axonal projections that exit a particular region; as opposed to afferent projections that arrive at the region. These terms have a slightly different meaning in the context of the peripheral nervous system (PNS) and central nervous system (CNS). The efferent fiber is a long process projecting far from the neuron's body that carries nerve impulses away from the central nervous system toward the peripheral effector organs (mainly muscles and glands). A bundle of these fibers is called a motor nerve or an efferent nerve.

Different physiological pathways may lead to shortness of breath including via ASIC chemoreceptors, mechanoreceptors, and lung receptors. It is thought that three main components contribute to dyspnea: afferent signals, efferent signals, and central information processing. It is believed the central processing in the brain compares the afferent and efferent signals; and dyspnea results when a "mismatch" occurs between the two: such as when the need for ventilation (afferent signaling) is not being met by physical breathing (efferent signaling). Afferent signals are sensory neuronal signals that ascend to the brain.

All of these sinuses drain into the efferent lymph vessels to exit the node at the hilum on the concave side.

Here, blood from the portal veins and the efferent arterioles are mixed and travel out of the kidneys through the efferent veins. Alternatively, blood can also flow towards the liver. Research indicates that kidneys of avian species receive approximately 10% to 15% of cardiac output. The renal blood of common ravens is composed of various molecules.

Elsevier Saunders, St. Louis, Mo, .Warrell D. A., Cox T. M., Firth J. D. (2010): The Oxford Textbook of Medicine (5th ed.). Oxford University Press In the CNS, afferent and efferent projections are determined from the perspective of any given brain region. That is, each brain region has its own unique set of afferent and efferent projections.

Motor innervation of this muscle is provided through the pharyngeal plexus of the CN X (vagal nerve), SVE (special visceral efferent) fibers.

A neuroeffector junction is a site where a motor neuron releases a neurotransmitter to affect a target—non-neuronal—cell. This junction functions like a synapse. However, unlike most neurons, somatic efferent motor neurons innervate skeletal muscle, and are always excitatory. Visceral efferent neurons innervate smooth muscle, cardiac muscle, and glands, and have the ability to be either excitatory or inhibitory in function.

The cell bodies for the facial nerve are grouped in anatomical areas called nuclei or ganglia. The cell bodies for the afferent nerves are found in the geniculate ganglion for taste sensation. The cell bodies for muscular efferent nerves are found in the facial motor nucleus whereas the cell bodies for the parasympathetic efferent nerves are found in the superior salivatory nucleus.

Diagram of the circulation related to a single glomerulus, associated tubule, and collecting system. The glomerulus receives its blood supply from an afferent arteriole of the renal arterial circulation. Unlike most capillary beds, the glomerular capillaries exit into efferent arterioles rather than venules. The resistance of the efferent arterioles causes sufficient hydrostatic pressure within the glomerulus to provide the force for ultrafiltration.

The efferent lymphatic vessel commences from the lymph sinuses of the medullary portion of the lymph nodes and leave the lymph nodes at the hilum, either to veins or greater nodes. It carries filtered lymph out of the node. Efferent lymphatic vessels are also found in the thymus and spleen. This is in contrast to afferent lymphatic vessels, which are found only in lymph nodes.

Each Edinger-Westphal nucleus gives rise to preganglionic parasympathetic fibers which exit with CN III and synapse with postganglionic parasympathetic neurons in the ciliary ganglion. Postganglionic nerve fibers leave the ciliary ganglion to innervate the ciliary sphincter. Each afferent limb has two efferent limbs, one ipsilateral and one contralateral. The ipsilateral efferent limb transmits nerve signals for direct light reflex of the ipsilateral pupil.

The glomerulus receives its blood supply from an afferent arteriole of the renal arterial circulation. Unlike most capillary beds, the glomerular capillaries exit into efferent arterioles rather than venules. The resistance of the efferent arterioles causes sufficient hydrostatic pressure within the glomerulus to provide the force for ultrafiltration. The glomerulus and its surrounding Bowman's capsule constitute a renal corpuscle, the basic filtration unit of the kidney.

Many pretectal nuclei share targets of efferent projections. All pretectal nuclei, except for the ON, project to nuclei in the thalamus, subthalamus, superior colliculus, reticular formation, pons, and inferior olive. Both the ON and the CPA have efferent projections to the Edinger- Westphal nucleus. The NPP and NPA both project to the pulvinar, the lateral posterior nucleus of the thalamus, and several precerebellar nuclei.

The somatic nervous system (SNS or voluntary nervous system) is the part of the peripheral nervous system associated with the voluntary control of body movements via skeletal muscles. The somatic nervous system consists of afferent nerves or sensory nerves, and efferent nerves or motor nerves. Afferent nerves are responsible for relaying sensation from the body to the central nervous system; efferent nerves are responsible for sending out commands from the CNS to the body, stimulating muscle contraction; they include all the non-sensory neurons connected with skeletal muscles and skin. The a- of afferent and the e- of efferent correspond to the prefixes ad- (to, toward) and ex- (out of).

Efferent fibers of the vagus then carry signals to the gastrointestinal tract up to two-thirds of the transverse colon (coinciding with the second GI watershed point).

Whenever these afferent nerve endings are stimulated (for example, by dust, cold air or fumes) impulses travel to the brain-stem vagal center, then down the vagal efferent pathway to again reach the bronchial small airways. Acetylcholine is released from the efferent nerve endings. This acetylcholine results in the excessive formation of inositol 1,4,5-trisphosphate (IP3) in bronchial smooth muscle cells which leads to muscle shortening and this initiates bronchoconstriction.

Didactic organisation is primarily a consequence of spike-timing-dependent plasticity, because when the neurons within an interconnected network undergo action potentials (or ‘spikes’) at approximately the same time (within the order of tens of milliseconds) the efferent synaptic connections of neurons that spike early will have their efficacy increased (long-term potentiation), while neurons that spike late will have the efficacy of their efferent synaptic connections decreased (long-term depression).

With a singular neuromuscular junction, each muscle fiber receives input from just one somatic efferent neuron. Action potential in a somatic efferent neuron causes the release of the neurotransmitter acetylcholine. When the acetylcholine is released it diffuses across the synapse and binds to a receptor on the sarcolemma, a term unique to muscle cells that refers to the cell membrane. This initiates an impulse that travels across the sarcolemma.

Efferent signals are the motor neuronal signals descending to the respiratory muscles. The most important respiratory muscle is the diaphragm. Other respiratory muscles include the external and internal intercostal muscles, the abdominal muscles and the accessory breathing muscles. As the brain receives its plentiful supply of afferent information relating to ventilation, it is able to compare it to the current level of respiration as determined by the efferent signals.

The neuromuscular junction is a specialized synapse between a neuron and the muscle it innervates. It allows efferent signals from the nervous system to contact muscle fibers causing them to contract. In vertebrates, the neuromuscular junction is always excitatory, therefore to stop contraction of the muscle, inhibition must occur at the level of the efferent motor neuron. In other words, the inhibition must occur at the level of the spinal cord.

Without teeth or folds, as the aperture in some gastropods. Efferent. Carrying out. Elliptical. With an oval form. Elongated. Drawn out, as the spire of a shell. Emarginate.

The blood circulation in the periphery, especially the radiole, is especially unusual. Instead of venous and arterial blood flowing through afferent and efferent vessels within the radiole, there is a single branchial sinus through which blood flows in both directions, in a tidal fashion. The vessels of the peripheral system receive their blood from the central system, returning it back along the same channels (i.e., these channels serve in both afferent and efferent directions).

Microneurography is a technique using metal electrodes to observe neural traffic of both myelinated and unmyelinated axons in efferent and afferent neurons of the skin and muscle. This technique is particularly important in research involving C fibers. Single action potentials from unmyelinated axons can be observed. Recordings from efferent postganglionic sympathetic C fibers of the muscles and skin yield insights into the neural control of autonomic effector organs like blood vessels and sweat glands.

Efferent projections from the brain to the cochlea also play a role in the perception of sound. Efferent synapses occur on outer hair cells and on afferent axons under inner hair cells. The presynaptic terminal bouton is filled with vesicles containing acetylcholine and a neuropeptide called calcitonin gene-related peptide. The effects of these compounds vary, in some hair cells the acetylcholine hyperpolarized the cell, which reduces the sensitivity of the cochlea locally.

Common coding posits, on top of separate coding, further domains of representation in which afferent and efferent information share the same format and dimensionality of representation. Common coding refers to 'late' afferent representations (referring to events in the environment) and 'early' efferent representations (referring to intended events). Such representations are commensurate since they both exhibit distal reference. They permit creating linkages between perception and action that do not rely on arbitrary mappings.

Situated within the arbor vitae are the deep cerebellar nuclei; the dentate, globose, emboliform and the fastigial nuclei. These four different structures lead to the efferent projections of the cerebellum.

The abducens nerve supplies the lateral rectus muscle of the human eye. This muscle is responsible for outward gaze. The abducens nerve carries axons of type GSE, general somatic efferent.

In a male, it develops into a system of connected organs between the efferent ducts of the testis and the prostate, namely the epididymis, the vas deferens, and the seminal vesicle. The prostate forms from the urogenital sinus and the efferent ducts form from the mesonephric tubules. For this it is critical that the ducts are exposed to testosterone during embryogenesis. Testosterone binds to and activates androgen receptor, affecting intracellular signals and modifying the expression of numerous genes.

Myelinated GS efferent fiber leaving cell body of motor neuron to form a neuromuscular junction The efferent nerve fibers of motor neurons are involved in muscle control, both skeletal and smooth muscle. The cell body of the motor neuron is connected to a single, long axon and several shorter dendrites projecting out of the cell body itself. This axon then forms a neuromuscular junction with the effectors. The cell body of the motor neuron is satellite-shaped.

Efference copies are created with our own movement but not those of other people. This is why other people can tickle us (no efference copies of the movements that touch us) but we cannot tickle ourselves (efference copies tell us that we are stimulating ourselves). In physiology, an efference copy or efferent copy is an internal copy of an outflowing (efferent), movement- producing signal generated by an organism's motor system.Jeannerod, Marc (2003): "Action Monitoring and Forward Control of Movements".

For example, a cortical efferent is a fibre coming from elsewhere, and arriving to the cortex. Note that that is the opposite of the direction in which the nerve fibre conducts signals.

The formation of cysts in the rete testis is associated with the obstruction of the efferent ducts, which connect the rete testis with the head of the epididymis. They are often bilateral.

Catecholamines (norepinephrine and epinephrine) increase filtration fraction by vasoconstriction of afferent and efferent arterioles, possibly through activation of alpha-1 adrenergic receptors. Severe haemorrhage will also result in an increased filtration fraction.

The abducens nerve (or abducent nerve) is the sixth cranial nerve (CNVI), in humans, that controls the movement of the lateral rectus muscle, responsible for outward gaze. It is a somatic efferent nerve.

The efferent projections (axonal output) of HSD2 neurons have been investigated to a significant degree using conventional neuroanatomical tracers. Their primary output targets are the pre-locus coeruleus (pre-LC), the innermost portion of the external lateral parabrachial subnucleus (PBel), and the anterior, ventrolateral bed nucleus of the stria terminalis (BSTvl). The next-order input and output connections of these target regions have been investigated in detail as well. Additional information about the efferent projections of HSD2 neurons can be found in ref.

Afferent nerve fibers refer to axonal projections that arrive at a particular brain region, as opposed to efferent projections that exit the region. These terms have a slightly different meaning in the context of the peripheral nervous system (PNS) and central nervous system (CNS). In the PNS, afferent and efferent projections are always from the perspective of the spinal cord (see figures). PNS afferents are the axons of sensory neurons carrying sensory information from all over the body, into the spine.

The facial nerve carries axons of type GSA, general somatic afferent, to skin of the posterior ear. The facial nerve also carries axons of type GVE, general visceral efferent, which innervate the sublingual, submandibular, and lacrimal glands, also mucosa of nasal cavity. Axons of type SVE, special visceral efferent, innervate muscles of facial expression, stapedius, the posterior belly of digastric, and the stylohyoid. The axons of type SVA, special visceral afferent, provide taste to the anterior two-thirds of tongue via chorda tympani.

The trigeminal motor nucleus forms the efferent pathway of the jaw jerk reflex. Since the axons involved in this reflex do not decussate, a lesion involving the trigeminal motor nucleus would cause ipsilateral hemiparesis.

The amygdalofugal pathway (Latin for "fleeing from the amygdala" and commonly distinguished as the ventral amygdalofugal pathway) is one of the three major efferent pathways of the amygdala, meaning that it is one of the three principal pathways by which fibers leave the amygdala. It leads from the basolateral nucleus and central nucleus of the amygdala. The amygdala is a limbic structure in the medial temporal lobe of the brain. The other main efferent pathways from the amygdala are the stria terminalis and anterior commissure.

The physical contractions of the smooth muscle cells can be caused by action potentials in efferent motor neurons of the enteric nervous system, or by receptor mediated calcium influx. These efferent motor neurons of the enteric nervous system are cholinergic and adrenergic neurons. The inner circular layer is innervated by both excitatory and inhibitory motor neurons, while the outer longitudinal layer is innervated by mainly excitatory neurons. These action potentials cause the smooth muscle cells to contract or relax, depending on the particular stimulation the cells receive.

The sympathetic ganglia, or autonomic ganglia, are the ganglia of the sympathetic nervous system. Ganglia are 20,000 to 30,000 afferent and efferent nerve cell bodies that run along on either side of the spinal cord. Afferent nerve cell bodies bring information from the body to the brain and spinal cord, while efferent nerve cell bodies bring information from the brain and spinal cord to the rest of the body. The cell bodies create long sympathetic chains that are on either side of the spinal cord.

Among investigators there is disagreement regarding the terminology used to describe the type of information carried by the accessory nerve. As the trapezius and sternocleidomastoid muscles are derived from the pharyngeal arches, some investigators believe the spinal accessory nerve that innervates them must carry specific special visceral efferent (SVE) information. This is in line with the observation that the spinal accessory nucleus appears to be continuous with the nucleus ambiguus of the medulla. Others consider the spinal accessory nerve to carry general somatic efferent (GSE) information.

The oculomotor nerve include axons of type GSE, general somatic efferent, which innervate skeletal muscle of the levator palpebrae superioris, superior rectus, medial rectus, inferior rectus, and inferior oblique muscles.(innervates all the extrinsic muscles except superior oblique and lateral rectus.) The nerve also includes axons of type GVE, general visceral efferent, which provide preganglionic parasympathetics to the ciliary ganglion. From the ciliary ganglion post ganglionic fibers pass through the short ciliary nerve to the constrictor pupillae of the iris and the cilliary muscles.

Utilizing F4/80 knockout mice, Lin et al. showed that F4/80 is not necessary for the development of tissue macrophages but is required for the induction of efferent CD8+ regulatory T cells needed for peripheral tolerance.

In anatomy and neurology, the ventral root or anterior root is the efferent motor root of a spinal nerve. At its distal end, the ventral root joins with the dorsal root to form a mixed spinal nerve.

The ventral anterior nucleus receives neuronal inputs from the basal ganglia. Its main afferent fibres are from the globus pallidus. The efferent fibres from this nucleus pass into the premotor cortex for initiation and planning of movement.

This blood leaves the glomerulus via the efferent arteriole, which supplies the peritubular capillaries. The higher osmolarity of the blood in the peritubular capillaries creates an osmotic pressure which causes the uptake of water. Other ions can be taken up by the peritubular capillaries via solvent drag. Water is also driven into the peritubular capillaries due to the higher fluid pressure of the interstitium, driven by reabsorption of fluid and electrolytes via active transport, and the low fluid pressure of blood entering the peritubular capillaries due to the narrowness of the efferent arteriole.

" Anchoring one end is Efferent reading, the most common kind, in which the reader seeks to derive information from the text. In this instance, a reader is concerned mainly or totally with the gist, the message, the information, he or she can "carry away," which is what "efferent" means, conducting away. Such a reader does not care about how the text is worded. In contrast, if a reader approaches a text seeking to enjoy its formal characteristics—its rhythms, its word choices, its images, its connotations—then that person is reading "aesthetically.

Due to the environment to which it is exposed, the posterior gills of the crab can also be cleared of parasites and sediment by increasing the movement of its fifth set of primitive legs. Each gill has a main axis with many lateral filaments or lamellae that are vascularized. The afferent channel transports blood from the gill axis into each filament through a fine afferent canal to the gill top. Blood returns by a minute efferent canal to the gill tip to the efferent channel and passes to the pericardial chamber, which contains the heart.

Blood exits the glomerular capillaries by an efferent arteriole instead of a venule, as is seen in the majority of capillary systems (Fig. 4). This provides tighter control over the blood flow through the glomerulus, since arterioles dilate and constrict more readily than venules, owing to their thick circular smooth muscle layer (tunica media). The blood exiting the efferent arteriole enters a renal venule, which in turn enters a renal interlobular vein and then into the renal vein. Cortical nephrons near the corticomedullary junction (15% of all nephrons) are called juxtamedullary nephrons.

The cholinergic anti-inflammatory pathway regulates the innate immune response to injury, pathogens, and tissue ischemia. It is the efferent, or motor arm of the inflammatory reflex, the neural circuit that responds to and regulates the inflammatory response.

Because it innervates muscles derived from pharyngeal arches, the facial motor nucleus is considered part of the special visceral efferent (SVE) cell column, which also includes the trigeminal motor nucleus, nucleus ambiguus, and (arguably) the spinal accessory nucleus.

The efferent arterioles of the undifferentiated cortical glomeruli are the most complex. Promptly on leaving the glomerulus they break up into capillaries and become part of a rich plexus of vessels surrounding the cortical portions of the renal tubules.

The juxtarestiform body carries both afferent and efferent fibers connecting the vestibular nuclei and the flocculonodular lobe and fastigial nucleus of the cerebellum. The juxtarestiform body coordinates balance and eye movements by communication between the vestibular apparatus and the cerebellum.

At the vascular pole, the afferent arterioles and efferent arterioles enter and leave the glomerulus in the Bowman's capsule. The tubular pole is at the other end opposite to the vascular pole. At the tubular pole, the proximal convoluted tubule arises.

In males, a few of the more caudal tubules will survive and give rise to the efferent ductules of the testis, the epididymis, vas deferens, seminal vesicle, as well as vestigial structures such as the appendix testis, appendix epididymis, and paradidymis.

The juxtaglomerular cells in the afferent arteriole constrict, and juxtaglomerular cells in both the afferent and efferent arteriole decrease their renin secretion. These actions function to lower GFR. Further increase in sodium concentration leads to the release of nitric oxide, a vasodilating substance, to prevent excessive vasoconstriction. In the opposite case, juxtaglomerular cells are stimulated to release more renin, which stimulates the renin–angiotensin system, producing angiotensin I which is converted by Angio- Tensin Converting Enzyme (ACE) to angiotensin II. Angiotensin II then causes preferential constriction of the efferent arteriole of the glomerulus and increases the GFR.

On the other hand, they acknowledge other factors too. The authors attribute feelings of agency to desirability of the results (see self serving biases) and top-down processing (reasoning and inferences about the situation). In this case, it is by the application of the forward model that one might imagine how other consciousness processes could be the result of efferent, predictive processing. If the conscious self is the efferent copy of actions and vetoes being performed, then the consciousness is a sort of narrator of what is already occurring in the body, and an incomplete narrator at that.

One of Unzer’s main contributions to science was the introduction of afferent and efferent reflexes. At its most basic level, afferent reflexes are those that move inward from something external, making its way to the central nervous system. Efferent then is the opposite, where the central nervous system triggers a reflex in the muscles. Unzer himself explains afferent reflexes: "To the end that an impression is felt…the external impression will have no other reflex action in the animal machines than that which is capable in virtue of its purely animal force, which it reflects upon the motor nerves…".

Male and female infertility has been observed in mice mutant for GEMC1, MCIDAS, or CCNO due to defective MCC differentiation. In females, MCC loss in the oviducts is the probable cause of infertility. The efferent duct epithelia of males contains MCCs that mobilize luminal fluids to prevent the agglutination of spermatozoa and promote fluid reabsorption. In mice mutant for these genes, degeneration of Sertoli cells, thinning of the seminiferous tubule epithelia, dilation of the rete testes and seminiferous tubules, sperm agglutinations in the efferent ducts, and lack of spermatozoa in the epididymis has been observed in conjunction with defects in MCC development.

Counter current multiplier diagram The loop of Henle is supplied by blood in a series of straight capillaries descending from the cortical efferent arterioles. These capillaries (called the vasa recta; recta is from the Latin for "straight") also have a countercurrent multiplier mechanism that prevents washout of solutes from the medulla, thereby maintaining the medullary concentration. As water is osmotically driven from the descending limb into the interstitium, it readily enters the capillaries. The low bloodflow through the vasa recta allows time for osmotic equilibration, and can be altered by changing the resistance of the vessels' efferent arterioles.

Staging of chronic kidney disease is based on categories of GFR as well as albuminuria and cause of kidney disease. Central to the physiologic maintenance of GFR is the differential basal tone of the afferent and efferent arterioles (see diagram). In other words, the filtration rate is dependent on the difference between the higher blood pressure created by vasoconstriction of the input or afferent arteriole versus the lower blood pressure created by lesser vasoconstriction of the output or efferent arteriole. GFR is equal to the renal clearance ratio when any solute is freely filtered and is neither reabsorbed nor secreted by the kidneys.

The hepatic venous pressure gradient, (difference in venous pressure between afferent and efferent blood to the liver) also determines the severity of cirrhosis, although it is hard to measure. A value of 16 mm or more means a greatly increased risk of death.

Afferent nerve fibers are often paired with efferent nerve fibers from the motor neurons (that travel from the CNS to the PNS), in mixed nerves. Stimuli cause nerve impulses in the receptors and alter the potentials, which is known as sensory transduction.

However, the OHCs and related processes are known to play a role.Zheng X-Y, Henderson D, McFadden SL, Hu B-H. The role of the cochlear efferent system in acquired resistance to noise-induced hearing loss. Hearing Research. 1997;104(1-2):191-203.

I. Cortical projection of the mediodorsal nucleus. II. Efferent connections. Brain Research, 12, 321-343 provided an anatomical basis for this possibility, leading to Kolb's demonstration that rodents have frontal areas that appear homologous to prefrontal areas in the primate.Kolb, B. (1984).

The efferent vessels of the subclavicular group unite to form the subclavian trunk, which opens either directly into the junction of the internal jugular and subclavian veins or into the jugular lymphatic trunk; on the left side it may end in the thoracic duct.

Extraglomerular mesangial cells are located in the junction between the afferent and efferent arterioles. These cells have a contractile property similar to vascular smooth muscles and thus play a role in “regulating GFR” by altering the vessel diameter. Renin is also found in these cells.

On the other hand, the seminiferous tubules are developed from the cords distal to the hilum, and between them connective-tissue septa extend. Via the rete testis, the seminiferous tubules become connected with outgrowths from the mesonephros, which form the efferent ducts of the testis.

The inhibition of calcineurin by cyclosporine and FK506 causes hypertension and hypertensive heart disease. Acutely, the neural mechanism is observed as the increase in blood pressure is accompanied by increased activity of efferent sympathetic nerve. The increased outflow of sympathetic efferents is a result of neural reflex due to the activation of renal and other subdiaphragmtic visceral afferents by calcineurin inhibitors. The fact that (1) the reflex activation of efferent sympathetic nerve activity and the increase in blood pressure by cyclosporine are attenuated in synapsin-deficient animal models and (2) synapsins are present in renal afferent/sensory nerve endings suggests that synapsins constitute putative substrates for calcineurin.

When angiotensin II levels are increased due to activation of the renin–angiotensin–aldosterone system, most of the arteries in the body experience vasoconstriction, in order to maintain adequate blood pressure. However, this reduces blood flow to the kidneys. To compensate, the efferent arterioles constrict to a greater degree than the other arteries, in response to increased levels of angiotensin II. Pressure in glomerular capillaries is therefore maintained and glomerular filtration rate remains adequate. However, in states of where angiotensin II is very high for a prolonged period of time, the colloid oncotic pressure of the capillaries will increase, counteracting the increased hydrostatic pressure from the efferent constriction.

In medicine, the colloquial term "touch" is usually replaced with "somatic senses" to better reflect the variety of mechanisms involved. Insensitivity to somatosensory stimuli, such as heat, cold, touch, and pain, are most commonly a result of a more general physical impairment associated with paralysis. Damage to the spinal cord or other major nerve fiber may lead to a termination of both afferent and efferent signals to varying areas of the body, causing both a loss of touch and a loss of motor coordination. Other types of somatosensory loss include hereditary sensory and autonomic neuropathy, which consists of ineffective afferent neurons with fully functioning efferent neurons; essentially, motor movement without somatosensation.

Functionally, however, the SFO may be viewed in two portions, the dorsolateral peripheral (pSFO) division and the ventromedial core segment. As an important mechanism of both energy and osmotic homeostasis, the SFO has many efferent projections. In fact, SFO neurons have been experimentally shown to broadcast efferent projections to regions involved in cardiovascular regulation including the lateral hypothalamus with fibers terminating in the supraoptic (SON) and paraventricular (PVN) nuclei, and the anteroventral 3rd ventricle (AV3V) with fibers terminating in the VOLT and the median preoptic area. It seems that the most essential of all these connections is the SFO’s projections to the paraventricular hypothalamic nucleus.

In the course of the lymph, lymphocytes may be activated as part of the adaptive immune response. There is usually only one efferent vessel though sometimes there may be two. Medullary sinuses contain histiocytes (immobile macrophages) and reticular cells. A lymph node contains lymphoid tissue, i.e.

Afferent nerve fibers leave the sensory neuron from the dorsal root ganglia of the spinal cord, and motor commands carried by the efferent fibers leave the cord at the ventral roots. The dorsal and some of the ventral fibers join as spinal nerves or mixed nerves.

The lymphatic drainage at the elbow is through the deep nodes at the bifurcation of the brachial artery, the superficial nodes drain the forearm and the ulnar side of the hand. The efferent lymph vessels from the elbow proceed to the lateral group of axillary lymph nodes.

The efferent impulses are then triggered by the medulla causing the signal to travel down the larynx and bronchial tree. This then triggers a cascade of events that involve the intercostal muscles, abdominal wall, diaphragm and pelvic floor which in conjunction together create the reflex known as coughing.

A spinal interneuron, found in the spinal cord, relays signals between (afferent) sensory neurons, and (efferent) motor neurons. Different classes of spinal interneurons are involved in the process of sensory-motor integration. Most interneurons are found in the grey column, a region of grey matter in the spinal cord.

The lesser petrosal nerve (also known as the small superficial petrosal nerve) is the general visceral efferent (GVE) component of the glossopharyngeal nerve (CN IX), carrying parasympathetic preganglionic fibers from the tympanic plexus to the parotid gland. It synapses in the otic ganglion, from where the postganglionic fibers emerge.

The blood exiting the efferent arterioles of these nephrons enter the vasa recta, which are straight capillary branches that deliver blood to the renal medulla. These vasa recta run adjacent to the descending and ascending loop of Henle, and participate in the maintenance of the medullary countercurrent exchange system.

As the light is being moved from one eye to another, both eyes begin to dilate, but constrict again when light has reached the other eye. If there is an efferent defect in the left eye, the left pupil will remain dilated regardless of where the light is shining, while the right pupil will respond normally. If there is an afferent defect in the left eye, both pupils will dilate when the light is shining on the left eye, but both will constrict when it is shining on the right eye. This is because the left eye will not respond to external stimulus (afferent pathway), but can still receive neural signals from the brain (efferent pathway) to constrict.

A motor signal from the central nervous system (CNS) to the periphery is called an efference, and a copy of this signal is called an efference copy. Sensory information coming from sensory receptors in the peripheral nervous system to the central nervous system is called afference. On a similar basis, nerves into the nervous system are afferent nerves and ones out are termed efferent nerves. When an efferent signal is produced and sent to the motor system, it has been suggested that a copy of the signal, known as an efference copy, is created so that exafference (sensory signals generated from external stimuli in the environment) can be distinguished from reafference (sensory signals resulting from an animal's own actions).

The subthalamus develops efferent (output) connections to the striatum (caudate nucleus and putamen) in the telencephalon, to the dorsal thalamus (medial and lateral nuclear groups) in the diencephalon, and to the red nucleus and substantia nigra in the mesencephalon. It receives afferent (input) connections from the substantia nigra and striatum.

The motor neuron is present in the grey matter of the spinal cord and medulla oblongata, and forms an electrochemical pathway to the effector organ or muscle. Besides motor nerves, there are efferent sensory nerves that often serve to adjust the sensitivity of the signal relayed by the afferent sensory nerve.

Glomerular mesangial cells structurally support the tufts. Blood enters the capillaries of the glomerulus by a single arteriole called an afferent arteriole and leaves by an efferent arteriole. The capillaries consist of a tube lined by endothelial cells with a central lumen. The gaps between these endothelial cells are called fenestrae.

The trophosome of vestimentiferans is a complex, multi-lobed body with a vascular blood system that covers the entire trunk region. Each lobule consists of a tissue of bacteriocytes enclosed by an aposymbiotic coelothel. It is traversed by an axial efferent blood vessel, and is supplied with ramifying peripheral afferent blood vessels.

Specific terms are used for peripheral nerves that originate from, or arrive at, a specific point. An afferent nerve fiber is a fibre originating at the present point. For example, a striatal afferent is an afferent originating at the striatum. An efferent nerve fiber is one that arrives at the present point.

There is a yellow circle around the blue rhinophores. The gills are colorless with a black line alone the afferent vessel and a yellow with black one along the efferent vessel. The tail is white with orange yellow lines and black spots, edged with blue. The sides of the foot bear yellow stripes.

The splanchnic nerves are paired visceral nerves (nerves that contribute to the innervation of the internal organs), carrying fibers of the autonomic nervous system (visceral efferent fibers) as well as sensory fibers from the organs (visceral afferent fibers). All carry sympathetic fibers except for the pelvic splanchnic nerves, which carry parasympathetic fibers.

The vagus nerve is the tenth cranial nerve. It regulates heart rate, broncho-constriction, digestion, and the innate immune response. The vagus nerve innervates the celiac ganglion, the site of origin of the splenic nerve. Stimulation of the efferent vagus nerve slows heart rate, induces gastrointestinal motility, and inhibits TNF production in spleen.

As intrafusal muscle fibers, nuclear chain fibers are innervated by both sensory afferents and motor efferents. The afferent innervation is via type Ia sensory fibers and type II sensory fibers. These project to the nucleus proprius in the dorsal horn of the spinal cord. Efferent innervation is via static γ motor neurons.

Mushroom Bodies of the Fruit Fly These regions are often modular and serve a particular role within the general systemic pathways of the nervous system. For example, the hippocampus is critical for forming memories in connection with many other cerebral regions. The peripheral nervous system also contains afferent or efferent nerves, which are bundles of fibers that originate from the brain and spinal cord, or from sensory or motor sorts of peripheral ganglia, and branch repeatedly to innervate every part of the body. Nerves are made primarily of the axons or dendrites of neurons (axons in case of efferent motor fibres, and dendrites in case of afferent sensory fibres of the nerves), along with a variety of membranes that wrap around and segregate them into nerve fascicles.

Simplified schema of basic nervous system function. Signals are picked up by sensory receptors and sent to the spinal cord and brain via the afferent leg of the peripheral nervous system, whereupon processing occurs that results in signals sent back to the spinal cord and then out to motor neurons via the efferent leg.

In the male the Wolffian duct persists, and forms for example the epididymis, the ductus deferens, the ejaculatory duct, seminal vesicle and efferent ducts. In the female, on the other hand, the Wolffian bodies and ducts atrophy, leaving behind only remnants in the adult, involving e.g. the development of the suspensory ligament of the ovary.

The feedback from the carotid body is sent to the cardiorespiratory centers in the medulla oblongata via the afferent branches of the glossopharyngeal nerve. The efferent fibres of the aortic body chemoreceptors are relayed by the vagus nerve. These centers, in turn, regulate breathing and blood pressure, with hypoxia causing an increase in ventilation.

For cortical nephrons, a single network of capillaries, known as the peritubular capillaries, surrounds the entire renal tubule, whereas for juxtamedullary nephrons, the peritubular capillaries surround only the proximal and distal convoluted tubules, while another network branching from the efferent arteriole, known as the straight arterioles of kidney, surrounds the nephron loop (of Henle).

Metcalfe, J., Eich, T. S., & Castel, A. D. (2010). "Metacognition of agency across the lifespan". Cognition, 267–282. These include a "forward model" in which the mind actually compares two signals to judge agency: the feedback from a movement, but also an "efferent copy" – a mental prediction of what that movement feedback should feel like.

The geniohyoid muscle is innervated by fibres from the first cervical nerve travelling alongside the hypoglossal nerve. Although the first three cervical nerves give rise to the ansa cervicalis, the geniohyoid muscle is said to be innervated by the first cervical nerve, as some of its efferent fibers do not contribute to ansa cervicalis.

Patients with chronic complete high cervical spinal cord lesions have intact efferent vagal neural pathways directed to the sinus node. However, an LF component can be detected in HRV and arterial pressure variabilities of some tetraplegic patients. Thus, the LF component of HRV in those without intact sympathetic inputs to the heart represent vagal modulation.

The efferent sensory neuron is the structure that carries the signal from the spinal cord back to the muscle. It carries the action potential from the ventral root of the spinal cord to the muscle down the alpha motor neuron. This synapses on the first structure discussed, the extrafusal fibers of the muscle spindle.

Schematic image of the hypoglossal nerve and innervation targets. The hypoglossal nerve provides motor control of the extrinsic muscles of the tongue: genioglossus, hyoglossus, styloglossus, and the intrinsic muscles of the tongue. These represent all muscles of the tongue except the palatoglossus muscle. The hypoglossal nerve is of a general somatic efferent (GSE) type.

A rapid response system (RRS) is a tool implemented in hospitals designed to identify and respond to patients with early signs of clinical deterioration on non-intensive care units with the goal of preventing respiratory or cardiac arrest. A RRS consists of two clinical components (afferent and efferent) and two organizational components (process improvement and administrative).

The reticulotegmental nucleus also receives efferent axons from the cerebellum. This nucleus is known for its large number of multipolar cells and its particularly reticular structure. The reticulotegmental nucleus is topographically related to pontine nuclei (non-reticular), being just dorsal to them. The reticulotegmental nucleus has been known to mediate eye movements, otherwise known as saccadic movement.

The lumbar ganglia are paravertebral ganglia located in the inferior portion of the sympathetic trunk. The lumbar portion of the sympathetic trunk typically has 4 lumbar ganglia. The lumbar splanchnic nerves arise from the ganglia here, and contribute sympathetic efferent fibers to the nearby plexuses. The first two lumbar ganglia have both white and gray rami communicates.

Microneurography recordings have elucidated the organization as well as normal and pathological function of a fair number of neural systems in man, whereas the technique is not useful in clinical routine for diagnostic purposes to clarify the condition of the individual patient. Three main groups of neural systems have been explored, i.e. proprioception, cutaneous sensibility, and sympathetic efferent activity.

The epididymis (; plural: epididymides or ) is a tube that connects a testicle to a vas deferens in the male reproductive system. It is present in all male reptiles, birds, and mammals. It is a single, narrow, tightly-coiled tube in adult humans, in length connecting the efferent ducts from the rear of each testicle to its vas deferens.

The rete testis ( ) is an anastomosing network of delicate tubules located in the hilum of the testicle (mediastinum testis) that carries sperm from the seminiferous tubules to the efferent ducts. It is the counterpart of the rete ovarii in females.Definition: Rete ovarii from Online Medical Dictionary Its function is to provide a site for fluid reabsorption.

They take these results to suggest that efferent motor commands, rather than just priority and consistency (see below), is key to self-agency attributions. Intentional binding may not be exclusive to self-agency, however; Strother, House, and Sukhvinder (2010) found intentional binding in a shared action situation where other agents with similar goals and actions were present.

The efferent arc occurs via the facial nerve. The reflex involves consensual blinking of both eyes in response to stimulation of one eye. This is due to the facial nerves' innervation of the muscles of facial expression, namely orbicularis oculi, responsible for blinking. Thus, the corneal reflex effectively tests the proper functioning of both cranial nerves V and VII.

The appendix of the epididymis (or pedunculated hydatid) is a small stalked appendage (sometimes duplicated) on the head of the epididymis. It is usually regarded as a detached efferent duct. This structure is derived from the Wolffian duct (Mesonephric Duct) as opposed to the appendix testis which is derived from the Müllerian duct (Paramesonephric Duct) remnant.

Amygdala is shown in purple. The amygdalofugal pathway (Latin for "fleeing from the amygdala" and commonly distinguished as the ventral amygdalofugal pathway) is one of the three principal pathways by which fibers leave the amygdala. The other main efferent pathways from the amygdala are the stria terminalis and anterior commissure. The anterior commissure also serves to connect the two amygdala.

It has been suggested that myofibroblasts also reside in the lamina propria of several organs. These cells have characteristics of both smooth muscle and fibroblasts. The lamina propria may also be rich in vascular networks, lymphatic vessels, elastic fibers, and smooth muscle fascicles from the muscularis mucosae. Afferent and efferent nerve endings can be found in the lamina propria as well.

Intrafusal muscle fibers are skeletal muscle fibers that serve as specialized sensory organs (proprioceptors) that detect the amount and rate of change in length of a muscle.Casagrand, Janet (2008) Action and Movement: Spinal Control of Motor Units and Spinal Reflexes. University of Colorado, Boulder. They constitute the muscle spindle and are innervated by both sensory (afferent) and motor (efferent) fibers.

Numerous experiments have demonstrated that electrical stimulation (ES) of the lumbosacral enlargement and dorsal root can induce locomotor EMG patterns and even hindlimb stepping in acute and chronic low-spinal animals and humans.Grillner S, Zangger P. 1984. The effect of dorsal root transection on the efferent motor pattern in the cat’s hindlimb during locomotion. Acta Physiologica Scandinavia. 120:393–405.

Efferent fibers of these nuclei terminates in cranial nerve nuclei involved in extraocular movement (oculomotor, trochlear, abducens), the cerebellum, and the thalamus. The perihypoglossal nuclei and their connections are part of a complex circuitry related to eye movements. Lesions in the nucleus prepositus impair the ability to keep the eyes fixed on a visual target, although conjugate movements are still performed accurately.

The autonomic nervous system is unique in that it requires a sequential two-neuron efferent pathway; the preganglionic neuron must first synapse onto a postganglionic neuron before innervating the target organ. The preganglionic, or first, neuron will begin at the “outflow” and will synapse at the postganglionic, or second, neuron's cell body. The postganglionic neuron will then synapse at the target organ.

In contrast, if the eyeball is actively moved by the eye muscles the world is perceived as still. The reasoning made is that with a passive movement of the eyeball, no efferent copies are made as with active movements that allow sensory changes to be anticipated and controlled for with the result in their absence the world appears to move.

Nerves that transmit signals from the brain are called motor or efferent nerves, while those nerves that transmit information from the body to the CNS are called sensory or afferent. Spinal nerves serve both functions and are called mixed nerves. The PNS is divided into three separate subsystems, the somatic, autonomic, and enteric nervous systems. Somatic nerves mediate voluntary movement.

Pharyngeal muscles are striated muscles of the head and neck. Unlike skeletal muscles that developmentally come from somites, pharyngeal muscles are developmentally formed from the pharyngeal arches. Most of the skeletal musculature supplied by the cranial nerves (special visceral efferent) is pharyngeal. Exceptions include, but are not limited to, the extraocular muscles and some of the muscles of the tongue.

The activated T cells then emigrate from the lymph nodes, via the efferent lymphatic vessel, and migrate around the body in the blood. In certain circumstances, some activated T cells show a preference for patrolling certain tissues. This has been termed lymphocyte homing. Gut-specific homing is the preferential movement of activated T cells to the intestine and the gut.

In human anatomy of the leg, the femoral sheath has three compartments. The lateral compartment contains the femoral artery, the intermediate compartment contains the femoral vein, and the medial and smallest compartment is called the femoral canal. The femoral canal contains efferent lymphatic vessels and a lymph node embedded in a small amount of areolar tissue. It is conical in shape and is about 2 cm long.

The afferent component, also known as the track-and-trigger system, uses standardized tools to track early signs of reversible clinical deterioration and trigger a call to the efferent component. Examples of afferent tools include single-parameter calling criteria and multi-parameter early warning scores. These tools can predict clinical deterioration based upon the patient’s trait (e.g. has epilepsy) and detect deterioration through the patient’s state (e.g.

The lateral vestibulospinal tract is a group of descending extrapyramidal motor neurons, or efferent nerve fibers. This tract is found in the lateral funiculus, a bundle of nerve roots in the spinal cord. The lateral vestibulospinal tract originates in the lateral vestibular nucleus or Deiters’ nucleus in the pons. The Deiters' nucleus extends from pontomedullary junction to the level of abducens nerve nucleus in the pons.

Visceral surface of the spleen Near the middle of the spleen is a long fissure, the hilum, which is the point of attachment for the gastrosplenic ligament and the point of insertion for the splenic artery and splenic vein. There are other openings present for lymphatic vessels and nerves. Like the thymus, the spleen possesses only efferent lymphatic vessels. The spleen is part of the lymphatic system.

H-reflex study uses stimulation of a nerve and recording the reflex electrical discharge from a muscle in the limb. This also evaluates conduction between the limb and the spinal cord, but in this case, the afferent impulses (those going toward the spinal cord) are in sensory nerves while the efferent impulses (those coming from the spinal cord) are in motor nerves. This process cannot be changed.

The spleen is a center of activity of the mononuclear phagocyte system and can be considered analogous to a large lymph node, as its absence causes a predisposition to certain infections. Like the thymus, the spleen has only efferent lymphatic vessels. Both the short gastric arteries and the splenic artery supply it with blood. The germinal centers are supplied by arterioles called penicilliary radicles.

As soon as the saccade concludes, another efferent cortical trigger is sent from the eyes back to the brain. This signal communicates to the brain that the saccade has concluded. Prompted by this signal, the visual cortex once again resumes processing visual information. For the student, his eyes have now reached the clock and his brain's visual cortex begins to process information from his eyes.

Prorenin () is a protein that constitutes a precursor for renin, the hormone that activates the renin–angiotensin system, which serves to raise blood pressure. Prorenin is converted into renin by the juxtaglomerular cells, which are specialised smooth muscle cells present mainly in the afferent, but also the efferent, arterioles of the glomerular capillary bed. Prorenin is a relatively large molecule, weighing approximately 46 KDa.

There are small afferent vessels (1) in cerata with puckerd membranous fringe on the inner sides. The vessels are leading to great median trunk. Efferent vessels (2), gland (3) a "normal" tissue of cerata (4). The circulatory system and respiratory system is unique in this animal, because nearly the whole of these vessels are distinctly visible on the skin of the back, rising above the general surface.

An important aspect of intelligent behavior as studied in AI is goal-based problem solving, a framework in which the solution to a problem can be described by finding a sequence of actions that lead to a desirable goal. A goal-seeking system is supposed to be connected to its outside environment by sensory channels through which it receives information about the environment and motor channels through which it acts on the environment. (The term "afferent" is used to describe "inward" sensory flows, and "efferent" is used to describe "outward" motor commands.) In addition, the system has some means of storing in a memory information about the state of the environment (afferent information) and information about actions (efferent information). Ability to attain goals depends on building up associations, simple or complex, between particular changes in states and particular actions that will bring these changes about.

Diagram showing the basic outline of nephron structure and function: diabetic nephropathy is associated with changes in the afferent and efferent arterioles, causing capillary hypertension; and damage to the glomerular capillaries of multiple causes, including mesangial matrix deposition The disease progression of diabetic nephropathy involves various clinical stages: hyperfiltration, microalbuminuria, macroalbuminuria, nephrotic proteinuria to progressive chronic kidney disease leading to end- stage renal disease (ESRD). The damage is exerted on all compartments of the kidney: the glomerulus, the renal tubules, the vasculature (afferent and efferent renal arterioles) and the interstitium. Renal fibrosis is the final common pathway of DN. This fibrosis is a product of multiple mechanisms including renal hemodynamic changes, glucose metabolism abnormalities associated with oxidative stress as well as inflammatory processes and an overactive renin-angiotensin-aldosterone system (RAAS). The pathophysiology of diabetic nephropathy is thought to involve an interaction between hemodynamic and metabolic factors.

The superior cerebellar peduncles (brachia conjunctiva) emerge from the cerebellum and ascend to form the lateral portion of the roof of the fourth ventricle, where they enter the brainstem below the inferior colliculi. They are bridged by the superior medullary velum. The superior cerebellar peduncles represent the main output route from the cerebellum, and as such, most of their fibers are efferent. A relatively small afferent contribution is present.

Pathway of a Monosynaptic Reflex The reflex pathway (reflex arc) is a sequence of neurons connecting the sensory input (afferent neuron) to the motor output (efferent neuron), resulting in a behavioral response. The general pathway of a spinal reflex is one which involves neurons contained within the spinal cord. However, the brain may also provide additional (supraspinal) contributions, which can modulate the responsiveness of the reflex to the sensory input.

The efferent portion is carried by the vagus nerve from the cardiovascular center of the medulla to the heart, of which increased stimulation leads to decreased output of the sinoatrial node. This reflex is especially sensitive in neonates and children, particularly during strabismus correction surgery. However, this reflex may also occur with adults. Bradycardia, junctional rhythm and asystole, all of which may be life- threatening, can be induced through this reflex.

Labeled diagram of human lymph node showing the flow of lymph. Afferent and efferent vessels Lymph enters the convex side of a lymph node through multiple afferent lymphatic vessels, which form a network of lymphatic vessels () and from here flows into a space () underneath the capsule called the subcapsular sinus. From here, lymph flows into sinuses within the cortex. After passing through the cortex, lymph then collects in medullary sinuses.

The efferent vessels of the tracheobronchial lymph nodes ascend upon the trachea and unite with efferents of the internal mammary and anterior mediastinal glands to form the right and left bronchomediastinal trunks. The right bronchomediastinal trunk may join the right lymphatic duct, and the left the thoracic duct, but more frequently they open independently of these ducts into the junction of the internal jugular and subclavian veins of their own side.

The cough reflex has both sensory (afferent) mainly via the vagus nerve and motor (efferent) components. Pulmonary irritant receptors (cough receptors) in the epithelium of the respiratory tract are sensitive to both mechanical and chemical stimuli. The bronchi and trachea are so sensitive to light touch that slight amounts of foreign matter or other causes of irritation initiate the cough reflex. The larynx and carina are especially sensitive.

The axons of subthalamic nucleus neurons leave the nucleus dorsally. The efferent axons are glutamatergic (excitatory). Except for the connection to the striatum (17.3% in macaques), most of the subthalamic principal neurons are multitargets and directed to the other elements of the core of the basal ganglia. Some send axons to the substantia nigra medially and to the medial and lateral nuclei of the pallidum laterally (3-target, 21.3%).

The lumbar trunks are formed by the union of the efferent vessels from the lateral aortic lymph nodes. They receive the lymph from the lower limbs, from the walls and viscera of the pelvis, from the kidneys and suprarenal glands and the deep lymphatics of the greater part of the abdominal wall. Ultimately, the lumbar trunks empty into the cisterna chyli, a dilatation at the beginning of the thoracic duct.

In the embryo, the epididymis develops from tissue that once formed the mesonephros, a primitive kidney found in many aquatic vertebrates. Persistence of the cranial end of the mesonephric duct will leave behind a remnant called the appendix of the epididymis. In addition, some mesonephric tubules can persist as the paradidymis, a small body caudal to the efferent ductules. A Gartner's duct is a homologous remnant in the female.

In the case of bladder control, contractions are controlled by the parasympathetic efferent pathways of the sacral section of the spine which renders lumbar stimulation ineffective. On the other hand, bladder control is closely associated with parasympathetic pathways on both the sacral and lumbar sections of the spine thus making sacro-lumbar anterior root stimulators a more viable option as it can deal with both sets of issues.

The basic MOC acoustic reflex. The auditory nerve responds to sound, sending a signal to the cochlear nucleus. Afferent nerve fibres cross the midline from the cochlear nucleus to the cell bodies of the MOCS (located near the MSOC), whose efferent fibres project back to the cochlea (red). In most mammals, the majority of the reflex is ipsilateral (shown as a thicker line), effectuated by the crossed MOCS.

He could write > perfectly well, but couldn't hold the pen because his hand was > shaking.British soldiers executed in First World War denied official pardon > at www.wsws.org It is now thought by professionals that Farr was possibly suffering from hyperacusis, which occurs when the olivocochlear bundle in the inner ear is damaged, causing it to lose its ability to soften and filter sound, making loud noises physically unbearable (auditory efferent dysfunction).

Stimulation of the efferent pathway of the vagus nerve releases acetylcholine, the neurotransmitter which interacts with the α7 subunit of the nicotinic AChR (α7 nAChR). nAChR is expressed on the cell membrane of macrophages and other cytokine secreting cells. Binding of acetylcholine to nAChR activates intracellular signal transduction which inhibits the release of pro-inflammatory cytokines. Ligand receptor signaling does suppress production of anti-inflammatory cytokines (IL-10).

Layer VI, the polymorphic or multiform layer, contains few large pyramidal neurons and many small spindle-like pyramidal and multiform neurons; layer VI sends efferent fibers to the thalamus, establishing a very precise reciprocal interconnection between the cortex and the thalamus.Creutzfeldt, O. 1995. Cortex Cerebri. Springer-Verlag. That is, layer VI neurons from one cortical column connect with thalamus neurons that provide input to the same cortical column.

The thalamic reticular nucleus receives input from the cerebral cortex and dorsal thalamic nuclei. Most input comes from collaterals of fibers passing through the thalamic reticular nucleus. Primary thalamic reticular nucleus efferent fibers project to dorsal thalamic nuclei, but never to the cerebral cortex. This is the only thalamic nucleus that does not project to the cerebral cortex, instead it modulates the information from other nuclei in the thalamus.

The Purkinje cells of the cerebellar cortex project into the deep cerebellar nuclei and inhibit the excitatory output system via GABAergic synapses. The fastigial nucleus receives its input from Purkinje cells in the vermis. Most of its efferent connections travel via the inferior cerebellar peduncle to the vestibular nuclei, which are located at the junction of the pons and the medulla oblongata. The fastigial nucleus sends excitatory projections beyond the cerebellum.

They also form para- or pre-vertebral gangalia of gross anatomy. The efferent nerve cell bodies bring information from the brain to the body regarding perceptions of danger. This perception of danger can instigate the fight-or-flight response associated with the sympathetic nervous system. The fight-or-flight response is adaptive when there is a real and present danger which can be avoided or diminished through increased sympathetic activity.

The basal ganglia contains many afferent glutamatergic inputs, with predominantly GABAergic efferent fibers, modulatory cholinergic pathways, significant dopamine in the pathways originating in the ventral tegmental area and substantia nigra, as well as various neuropeptides. Neuropeptides found in the basal ganglia include substance P, neurokinin A, cholecystokinin, neurotensin, neurokinin B, neuropeptide Y, somatostatin, dynorphin, enkephaline. Other neuromodulators found in the basal ganglia include nitric oxide, carbon monoxide, and phenylethylamine.

There are small efferent vessels in cerata with puckered membranous fringe on the inner sides. The vessels are leading to the great median trunk. Ceras, plural Cerata, are anatomical structures found externally in nudibranch sea slugs, especially in aeolid nudibranchs, marine opisthobranch gastropod mollusks in the clade Aeolidida. The singular of cerata is ceras, which comes from the Greek word "κέρας", meaning "horn", a reference to the shape of these structures.

Due to this interaction, dendritic cells move to the T cell zone or to the B cell follicle along the fibroblast reticular cell network. Dendritic cells exhibit C-type lectin receptors (CLEC-2), which bind to gp38 on the surface of lymphatic endothelial cells. Lymphocytes leave the lymph node, as effector immune cells, via the efferent lymph vessels. Their numbers compensate for the removal of dead peripheral lymphocytes.

There are two types: autonomic reflex arc (affecting inner organs) and somatic reflex arc (affecting muscles). Autonomic reflexes sometimes involve the spinal cord and some somatic reflexes are mediated more by the brain than the spinal cord. During a somatic reflex, nerve signals travel along the following pathway: # Somatic receptors in the skin, muscles and tendons # Afferent nerve fibers carry signals from the somatic receptors to the posterior horn of the spinal cord or to the brainstem # An integrating center, the point at which the neurons that compose the gray matter of the spinal cord or brainstem synapse # Efferent nerve fibers carry motor nerve signals from the anterior horn to the muscles # Effector muscle innervated by the efferent nerve fiber carries out the response. A reflex arc, then, is the pathway followed by nerves which (a.) carry sensory information from the receptor to the spinal cord, and then (b.) carry the response generated by the spinal cord to effector organs during a reflex action.

The lymphatic vessels follow the arteries in a retrograde fashion. The anterior lymphatic vessels drain into the pancreatoduodenal lymph nodes located along the superior and inferior pancreatoduodenal arteries and then into the pyloric lymph nodes (along the gastroduodenal artery). The posterior lymphatic vessels pass posterior to the head of the pancreas and drain into the superior mesenteric lymph nodes. Efferent lymphatic vessels from the duodenal lymph nodes ultimately pass into the celiac lymph nodes.

Obligate ram ventilation is also true of some pelagic bony fish species. The respiration and circulation process begins when deoxygenated blood travels to the shark's two-chambered heart. Here the shark pumps blood to its gills via the ventral aorta artery where it branches into afferent brachial arteries. Reoxygenation takes place in the gills and the reoxygenated blood flows into the efferent brachial arteries, which come together to form the dorsal aorta.

The trigeminal nucleus also sends efferent projections to the inferior olive (IO), and this represents the US pathway for EBC. The critical region of the IO for eyeblink conditioning is the dorsal accessory olive (Brodal, 1981), and climbing fibers (CF) from this region send information about the US to the cerebellum (Brodal, Walberg & Hoddevik, 1975; Thompson, 1989). Climbing fibers ultimately project to both the deep cerebellar nuclei and Purkinje cells (PCs) in the cerebellar cortex.

Therefore, in response to the electrical stimulations provided by the efferent nerve supply, they can alter in length, shape and stiffness. These changes influence the response of the basilar membrane to sound. It is therefore clear that the OHCs play a major role in the active processes of the cochlea. The main function of the active mechanism is to finely tune the basilar membrane, and provide it with a high sensitivity to quiet sounds.

This is certainly not the case. Pallidum is precisely one cerebral place where there is a dramatic change between one afferent geometry and a completely different efferent one. The inmap and the outmap are totally different. This is an indication of the fundamental role of the pallidonigral set: the spatial reorganisation of information for a particular "function", which is predictably a particular reorganisation within the thalamus preparing a distribution to the cortex.

During embryonic development, pseudounipolar neurons begin as bipolar in shape but become pseudounipolar as they mature. Common examples are the retina bipolar cell, the ganglia of the vestibulocochlear nerve,Bipolar+cell at eMedicine Dictionary the extensive use of bipolar cells to transmit efferent (motor) signals to control muscles, olfactory receptor neurons in the olfactory epithelium for smell (axons form the olfactory nerve), and neurons in the spiral ganglion for hearing (CN VIII).

The exact mechanism of action in parkinsonian syndromes is not precisely understood, but it is known that trihexyphenidyl blocks efferent impulses in parasympathetically innervated structures like smooth muscles (spasmolytic activity), salivary glands, and eyes (mydriasis). In higher doses direct central inhibition of cerebral motor centers may contribute. In very high doses central toxicity as seen in atropine overdose is noted. It binds to the M1 muscarinic receptor and possibly the dopamine receptor.

Certainly, brain damage to these regions seems to impair the ability of animals to path integrate. David Redish states that "The carefully controlled experiments of Mittelstaedt and Mittelstaedt (1980) and Etienne (1987) have demonstrated conclusively that this ability [path integration in mammals] is a consequence of integrating internal cues from vestibular signals and motor efferent copy".Redish, 1999. p67. Mice use place cells and grid cells in the brain's hippocampus region to perform path integration.

As of 2017 little was understood about exactly how vagal nerve stimulation modulates mood and seizure control. The vagus is the tenth cranial nerve and arises from the medulla; it carries both afferent and efferent fibers. The afferent vagal fibers connect to the nucleus of the solitary tract which in turn projects connections to other locations in the central nervous system. Proposed mechanisms include an anti- inflammatory effect, as well as changes in monoamines.

However, there is some increase with age. Counter-intuitively, there seems to be only a weak and barely significant correlation between sympathetic efferent activity and hypertension as found in group studies. In 1998, microneurography recordings were performed for the first time on a spaceflight aboard the Space Shuttle Columbia with the purpose to explore the effect of microgravity on the human sympathetic nerve system. Two astronauts measured MSNA from peroneal nerves of their fellow astronauts.

Obligate ram ventilation is also true of some pelagic bony fish species. The respiration and circulation process begins when deoxygenated blood travels to the shark's two-chambered heart. Here the shark pumps blood to its gills via the ventral aorta artery where it branches into afferent brachial arteries. Reoxygenation takes place in the gills and the reoxygenated blood flows into the efferent brachial arteries, which come together to form the dorsal aorta.

Spinal nerve Typical spinal nerve location Each spinal nerve is a mixed nerve, formed from the combination of nerve fibers from its dorsal and ventral roots. The dorsal root is the afferent sensory root and carries sensory information to the brain. The ventral root is the efferent motor root and carries motor information from the brain. The spinal nerve emerges from the spinal column through an opening (intervertebral foramen) between adjacent vertebrae.

The lymph capillaries drain the lymph to larger contractile lymphatics, which have valves as well as smooth muscle walls. These are called the collecting lymphatics. As the collecting lymph vessel accumulates lymph from more and more lymph capillaries in its course, it becomes larger and is called the afferent lymph vessel as it enters a lymphs node. Here the lymph percolates through the lymph node tissue and is removed by the efferent lymph vessel.

There is a noticeable enlargement of the epididymides in vasectomized men. This is probably due to increased backpressure within the vas deferens on the testicular side following its blockage by vasectomy. The efferent ducts and seminiferous tubules of the testes are also affected by backpressure, leading to an increase in area and thickness. Backpressure from blockage of the vas deferens causes a rupture in the epididymis, called an "epididymal blowout", in 50% of vasectomy patients.

The glossopharyngeal nerve, known as the ninth cranial nerve (CN IX), is a mixed nerve that carries afferent sensory and efferent motor information. It exits the brainstem out from the sides of the upper medulla, just anterior (closer to the nose) to the vagus nerve. The motor division of the glossopharyngeal nerve is derived from the basal plate of the embryonic medulla oblongata, while the sensory division originates from the cranial neural crest.

The trochlear nerve provides motor supply to the superior oblique muscle of the eye, The trochlear nerve carries axons of type GSE, general somatic efferent, which innervate skeletal muscle of the superior oblique muscle. The superior oblique muscle ends in a tendon that passes through a fibrous loop, the trochlea, located anteriorly on the medial aspect of the orbit. Trochlea means “pulley” in Latin; the fourth nerve is named after this structure.

The NOT has efferent projections to the zona incerta of the subthalamus, several nuclei of the pons, medulla, intralaminar nuclei, midbrain, and dorsal and ventral thalamic nuclei. Its bilateral inhibitory projections to the accessory optic system include connections to the lateral and medial terminal nuclei. Projections to the subthalamus are target toward the lateral geniculate nucleus and pulvinar. The NOT projects bilaterally to the superior colliculus, although the ipsilateral connections appear to be more dominant.

A single taste bud is innervated by several afferent nerves, while a single efferent fiber innervates several taste buds. Fungiform papillae are present on the anterior portion of the tongue while circumvallate papillae and foliate papillae are found on the posterior portion of the tongue. The salivary glands are responsible for keeping the taste buds moist with saliva. A single taste bud is composed of four types of cells, and each taste bud has between 30 and 80 cells.

The medial geniculate nucleus (MGN) or medial geniculate body (MGB) is part of the auditory thalamus and represents the thalamic relay between the inferior colliculus (IC) and the auditory cortex (AC). It is made up of a number of sub-nuclei that are distinguished by their neuronal morphology and density, by their afferent and efferent connections, and by the coding properties of their neurons. It is thought that the MGN influences the direction and maintenance of attention.

Information from other senses such as echolocation and magnetoreception may also be integrated in certain animals. The hippocampus is the part of the brain that integrates linear and angular motion to encode a mammal's relative position in space. David Redish states that "The carefully controlled experiments of Mittelstaedt and Mittelstaedt (1980) and Etienne (1987) have demonstrated conclusively that [path integration in mammals] is a consequence of integrating internal cues from vestibular signals and motor efferent copy".

In mammals, an elegant rete mirabile in the efferent arterioles of juxtamedullary glomeruli is important in maintaining the hypertonicity of the renal medulla. It is the hypertonicity of this zone, resorbing water osmotically from the renal collecting ducts as they exit the kidney, that makes possible the excretion of a hypertonic urine and maximum conservation of body water. Vascular retia mirabilia are also found in the limbs of a range of mammals. These reduce the temperature in the extremities.

The roots terminate in dorsal root ganglia, which are composed of the cell bodies of the corresponding neurons. Ventral roots consist of efferent fibers that arise from motor neurons whose cell bodies are found in the ventral (or anterior) gray horns of the spinal cord. The spinal cord (and brain) are protected by three layers of tissue or membranes called meninges, that surround the canal . The dura mater is the outermost layer, and it forms a tough protective coating.

The first scientific research study looking at corollary discharge was done by Descartes in 1664 when he published his book the Treatise of Man . He was studying apparent motion and developed early theories in an error of the mind to account for efferent signals centuries before corollary discharge theories developed. In his experiment he would take his finger and press it on the side of his eye. In doing this he would move the image across his retina.

Giszter, S. F., Moxon, K. A., Rybak, I. A., & Chapin, J. K. (2001). Neurobiological and neurorobotic approaches to control architectures for a humanoid motor system. Robotics and Autonomous Systems, 37(2-3), 219-235. This theory of motor action is based on the organization of cortical columns, which progressively integrate from simple sensory input into a complex afferent signals, or from complex motor programs to simple controls for each muscle fiber in efferent signals, forming a similar hierarchical structure.

Superficial neuromasts are located externally on the surface of the body, while canal neuromasts are located along the lateral lines in subdermal, fluid filled canals. Each neuromast consists of receptive hair cells whose tips are covered by a flexible and jellylike cupula. Hair cells typically possess both glutamatergic afferent connections and cholinergic efferent connections. The receptive hair cells are modified epithelial cells and typically possess bundles of 40-50 microvilli "hairs" which function as the mechanoreceptors.

The neurons present in the global pallidus and substantia nigra are the main output areas of the basal ganglia. These efferent neurons influence activity of the upper motor neurons. Neurons in these areas are GABAergic, and thus the main output of the basal ganglia is inhibitory, and spontaneous activation of these neurons consistently prevents unwanted movement. The input of medium spiny neurons to these output areas of the basal ganglia are also GABAergic and therefore inhibitory.

An efferent suppression of N1 was also observed by stimulating the MOCS cells bodies in the medial SOC, confirming that the N1 suppression was the result of MOC (not LOC) stimulation. More recently, several researchers have observed a suppression of cochlear neural output during stimulation of the inferior colliculus (IC) in the midbrain, which projects to the superior olivary complex (SOC) (Rajan, 1990; Mulders and Robertson, 2000; Ota et al., 2004; Zhang and Dolan, 2006). Ota et al.

Gentsch and Schütz-Bosbach (2011) find top–down modulation of visual event-related potentials (ERPs) by both self agency and priming of self-agency, suggesting that both efferent information and prior thoughts about action consequence inform the sense of agency. Furthermore, Engbert et al. (2008) showed that intentional binding occurred only when the movement of the response lever was actively generated by the subject; passive movements (initiated by the response lever) did not result in intentional binding.

The ganglion also consists of sympathetic efferent (postganglionic) fibers from the superior cervical ganglion. These fibers, from the superior cervical ganglion, travel through the carotid plexus, and then through the deep petrosal nerve. The deep petrosal nerve (carrying postganglionic sympathetics) joins with the greater petrosal nerve (carrying preganglionic parasympathetics) to form the nerve of the pterygoid canal, which passes through the pterygoid canal before entering the ganglion. The Stellate Ganglion is at the bottom of the Cervical Sympathetic Chain.

Polypterus ornatipinnis Polypterids possess paired lungs which connect to the esophagus via a glottis. They are facultative air-breathers, accessing surface air to breathe when the water they inhabit is poorly oxygenated. Their lungs are highly vascularized to facilitate gas exchange. Deoxygenated arterial blood is brought to the lungs by paired pulmonary arteries, which branch from the fourth efferent branchial arteries (artery from the fourth gill arch), and oxygenated blood leaves the lungs in pulmonary veins.

These fibers synapse in the pterygopalatine ganglion, whereupon the postganglionic, postsynaptic, efferent fibers travel to innervate the lacrimal gland and the mucosal glands of the nose, palate, and pharynx. Preganglionic parasympathetic fibers are also distributed partly via the chorda tympani and lingual nerves to the submandibular ganglion, thence by postganglionic (vasodilator) fibers to the submandibular and sublingual salivary glands. The term "lacrimal nucleus" is sometimes used to refer to a portion of the superior salivatory nucleus.

The CNS consists of the brain and spinal cord. The PNS consists mainly of nerves, which are enclosed bundles of the long fibers or axons, that connect the CNS to every other part of the body. Nerves that transmit signals from the brain are called motor or efferent nerves, while those nerves that transmit information from the body to the CNS are called sensory or afferent. Spinal nerves serve both functions and are called mixed nerves.

Symptoms also can mimic a neoplasm with symptoms such as headaches, aphasia, and/ or seizures.[13] There are some differences with normal MS symptoms. Spasticity is not as prevalent in tumefactive cases, because in standard MS it is caused by demyelination or inflammation in the motor areas of the brain or the spinal cord. This upper motor neuron syndrome appears when motor control of skeletal muscles is affected due to damage to the efferent motor pathways.

These divisions are summarized below in Divisions of the premotor cortex. The connectivity of the premotor cortex is diverse, partly because the premotor cortex itself is heterogenous and different subregions have different connectivity. Generally the premotor cortex has strong afferent (input) and efferent (output) connectivity to the primary motor cortex, the supplementary motor area, the superior and inferior parietal cortex, and prefrontal cortex. Subcortically it projects to the spinal cord, the striatum, and the motor thalamus among other structures.

Beta motor neurons (β motor neurons), also called beta motoneurons, are a kind of lower motor neuron, along with alpha motor neurons and gamma motor neurons. Beta motor neurons innervate intrafusal fibers of muscle spindles with collaterals to extrafusal fibers - a type of slow twitch fiber. Also, axons of alpha, beta, and gamma motor neurons become myelinated. Moreover, these efferent neurons originate from the anterior grey column of the spinal cord and travel to skeletal muscles.

As enteric afferent and efferent nerves do not protrude into the intestinal lumen, EC cells act as a form of sensory transduction. Serotonin in the ENS acts in synergy with other digestive hormones to regulate sensory and motor gastrointestinal reflexes. EC cells respond to both chemical and neurological stimuli. They are also reactive to mechanosensation, which is the case in the peristaltic reflex of the gut, and can be stimulated by a bolus moving through the bowel.

However, this second efferent trigger also communicates to the brain that a period of time has been missing from perception. To fill this gap in perception, visual information is processed in a manner known as neural antedating or backdating. In this visual processing, the gap in perception is “filled in” with information gathered after the saccade. For the student, the gap of time that occurred during the saccade is substituted with the processed image of the clock.

Together with turtles, the tuatara has the most primitive hearing organs among the amniotes. There is no eardrum and no earhole, they lack a tympanum, and the middle ear cavity is filled with loose tissue, mostly adipose (fatty) tissue. The stapes comes into contact with the quadrate (which is immovable), as well as the hyoid and squamosal. The hair cells are unspecialised, innervated by both afferent and efferent nerve fibres, and respond only to low frequencies.

The putamen is interconnected with the following structures: This is a transverse section of the striatum from a structural MR image. The striatum includes the caudate nucleus (top) and putamen (right) and the globus pallidus (left). This description is rudimentary and does not nearly exhaust even the basic established circuitry of the putamen. The cortico-subcortico-cortical circuits with putaminal involvement are dense and complicated, consisting of a wide range of axonal, dendritic, chemical, afferent, and efferent substrates.

In medicine these proteins are useful and are used as a mitogen to trigger T-lymphocyte cell division and to activate latent HIV-1 from human peripheral lymphocytes. In neuroscience, anterograde tracing is a research method that uses the protein product phytohaemagglutinin PHA-L as a molecular tracer that can be taken up by the cell and transported across the synapse into the next cell thereby tracing the path of axonal projections and relative connections that nerve impulses travel beginning with the source located at the perikaryon (cell body or soma) and through the presynaptic part located on neuron's efferent axon all the way to the point of termination at the efferent synapse which then provides input to another neuron. Lymphocytes cultured with phytohaemagglutinin can be used for karyotype analysis. Stimulation of peripheral blood lymphocytes by phytohaemagglutinin presents a classic model of transition of cells from the quiescent G0 phase of the cell cycle into G1-, and subsequently progression through S-, G2- and M- phases of the cycle.

The ventral pallidum lies within the substantia innominata (Latin for unnamed substance) and receives efferent connections from the ventral striatum (the nucleus accumbens and the olfactory tubercle). It projects to the dorsomedial nucleus of the dorsal thalamus, which, in turn, projects to the prefrontal cortex; it also projects to the pedunculopontine nucleus and tegmental motor areas. Its function is to serve as a limbic- somatic motor interface, and it is involved in the planning and inhibition of movements from the dorsal striatopallidal complex.

Only two patients are recorded as having no complications.; ; ; The theoretical basis of Burckhardt's action rested on three propositions. The first was that mental illness had a physical basis and that disordered minds were merely a reflection of disordered brains. Next, the associationist viewpoint of nerve functioning which conceived the nervous system as operating according to the following threefold division of labor: an input (or sensory or afferent) system, a connecting system which processed information and an output (or efferent or motor) system.

Lumbar plexus and its branches. Since the Lumbar plexus and Sacral plexus are interconnected, they are sometimes referred to as the Lumbosacral plexus. The intercostal nerves that give rami to the chest and to the upper parts of the abdominal wall efferent motor innervation and to the pleura and peritoneum afferent sensory innervation are the only ones that do not originate from a plexus. The ventral rami of L1-L5 spinal nerves with a contribution of T12 form Lumbar plexus.

Motor information travels from the brain down the spinal cord via descending spinal cord tracts. Descending tracts involve two neurons: the upper motor neuron (UMN) and lower motor neuron (LMN).Saladin. Anatomy and Physiology, 5th Ed. A nerve signal travels down the upper motor neuron until it synapses with the lower motor neuron in the spinal cord. Then, the lower motor neuron conducts the nerve signal to the spinal root where efferent nerve fibers carry the motor signal toward the target muscle.

Unzer was one of the first to confront this problem. Using what he had observed from animals and their reactions to beheading, he concluded that the same phenomena could be applied to human beings as well. He said that if a signal had nowhere to go (i.e. once it reached the place where the head was severed), it may travel back through an efferent pathway, causing the motion that the person would have performed if he or she were whole.

The male reproductive system includes testes, rete testis, efferent ductules, epididymis, sex accessory glands, sex accessory ducts and external genitalia. Testosterone, an androgen, although present in both males and females, is relatively more abundant in males. Testosterone serves as one of the major sexual reproductive hormones in the male reproductive system However, the enzyme aromatase is present in testes and capable of synthesizing estrogens from androgens. Estrogens are present in high concentrations in luminal fluids of the male reproductive tract.

Thus, any stretching of a muscle automatically signals a reflexive contraction of that muscle, without any central control. As the name and the description implies, monosynaptic reflexes depend on a single synaptic connection between an afferent sensory neuron and efferent motor neuron. In general the actions of monosynaptic reflexes are fixed and cannot be controlled or influenced by intention or instruction. However, there is some evidence to suggest that the gain or magnitude of these reflexes can be adjusted by context and experience.

The inner portion of the node is called the medulla, which is surrounded by the cortex on all sides except for a portion known as the hilum. The hilum presents as a depression on the surface of the lymph node, causing the otherwise spherical lymph node to be bean-shaped or ovoid. The efferent lymph vessel directly emerges from the lymph node at the hilum. The arteries and veins supplying the lymph node with blood enter and exit through the hilum.

The pyramidal tracts include both the corticobulbar tract and the corticospinal tract. These are aggregations of efferent nerve fibers from the upper motor neurons that travel from the cerebral cortex and terminate either in the brainstem (corticobulbar) or spinal cord (corticospinal) and are involved in the control of motor functions of the body. The corticobulbar tract conducts impulses from the brain to the cranial nerves.Chapter 9 of "Principles of Physiology" (3rd edition) by Robert M. Berne and Mathew N. Levy.

The nerve axons traveling down the tract are the efferent nerve fibers of the upper motor neurons. These axons travel down the tracts in the white matter of the spinal cord until they reach the vertebral level of the muscle that they will innervate. At this point, the axons synapse with lower motor neurons. The majority of axons do not directly synapse with lower motor neurons, but instead synapse with an interneuron that then synapses with a lower motor neuron.

The neuroepithlium is located at the top of the nasal vault, which is at the upper portion of the nasal septum. The information received by the olfactory receptors is transmitted by the olfactory nerves to the olfactory bulb through the cribriform plate. In the olfactory bulb, olfactory nerves make synaptic contact with dendrites of mitral and tufted cells. Efferent neurons of the olfactory bulb become the fibers that form the olfactory tracts, which is directly under the frontal lobes in the brain.

The mechanoreceptive hair cells of the lateral line structure are integrated into more complex circuits through their afferent and efferent connections. The synapses that directly participate in the transduction of mechanical information are excitatory afferent connections that utilize glutamate. However, a variety of different neuromast and afferent connections are possible, resulting in variation in mechanoreceptive properties. For instance, a series of experiments on the superficial neuromasts of Porichthys notatus revealed that neuromasts can exhibit a receptive specificity for particular frequencies of stimulation.

After burrowing their way through the liver tissue, they again use the efferent blood stream to carry them to the lungs. There, they get stuck in the capillaries surrounding the lungs and they penetrate the lung alveoli. It takes approximately 7 days to reach the lungs. Once the larvae are inside the lung, they migrate up the respiratory tree and are eventually coughed up and swallowed by the host to reach the small intestine again as soon as 10 days after infection.

The choice phase involves efferent codes, which uses muscle groups that contribute to a response. These coding systems are functionally different but interact to create a positive feedback loop in auditory functioning. This linking between perception and response in a speech shadowing task can be enhanced by the instructions given to participants. Analysing the variations of instructions of shadowing tasks concludes that through each case, the motor systems are primed to respond optimally and reduce a delay in reaction time.

The superior cerebellar peduncle is mainly an output to the cerebral cortex, carrying efferent fibers via thalamic nuclei to upper motor neurons in the cerebral cortex. The fibers arise from the deep cerebellar nuclei. The middle cerebellar peduncle is connected to the pons and receives all of its input from the pons mainly from the pontine nuclei. The input to the pons is from the cerebral cortex and is relayed from the pontine nuclei via transverse pontine fibers to the cerebellum.

The middle peduncle is the largest of the three and its afferent fibers are grouped into three separate fascicles taking their inputs to different parts of the cerebellum. The inferior cerebellar peduncle receives input from afferent fibers from the vestibular nuclei, spinal cord and the tegmentum. Output from the inferior peduncle is via efferent fibers to the vestibular nuclei and the reticular formation. The whole of the cerebellum receives modulatory input from the inferior olivary nucleus via the inferior cerebellar peduncle.

The olivocochlear bundle (OCB) originates in the superior olivary complex in the brainstem. The vestibulocochlear anastomosis carries the efferent axons into the cochlea, where they innervate the organ of Corti (OC). The OCB contains fibres projecting to both the ipsilateral and contralateral cochleae, prompting an initial division into crossed (COCB) and uncrossed (UCOCB) systems. More recently, however, the division of the OCB is based on the cell bodies’ site of origin in the brainstem relative to the medial superior olive (MSO).

These studies have measured the output of the auditory nerve (AN), with and without OCB stimulation. In 1956, Galambos activated the efferent fibres of the cat by delivering shock stimuli to the floor of the fourth ventricle (at the decussation of the COCB). Galambos observed a suppression of the compound action potentials of the AN (referred to as the N1 potential) evoked by low-intensity click stimuli. This basic finding was repeatedly confirmed (Desmedt and Monaco, 1961; Fex, 1962; Desmedt, 1962; Wiederhold, 1970).

The vasa recta of the kidney, (vasa rectae renis) are the straight arterioles, and the straight venules of the kidney, – a series of blood vessels in the blood supply of the kidney that enter the medulla as the straight arterioles, and leave the medulla to ascend to the cortex as the straight venules. (Latin: vasa, "vessels"; recta, "straight"). They lie parallel to the loop of Henle. These vessels branch off the efferent arterioles of juxtamedullary nephrons (those nephrons closest to the medulla).

The solitary tract conveys afferent information from stretch receptors and chemoreceptors in the walls of the cardiovascular, respiratory, and intestinal tracts. Afferent fibers from cranial nerves 7, 9 and 10 convey taste (SVA) in its rostral portion, and general visceral sense (general visceral afferent fibers, GVA) in its caudal part. Taste buds in the mucosa of the tongue can also generate impulses in the rostral regions of the solitary tract. The efferent fibers are distributed to the solitary tract nucleus.

The DCN differs from the ventral portion of the CN as it not only projects to the central nucleus (a subdivision) of the inferior colliculus (CIC), but also receives efferent innervation from the auditory cortex, superior olivary complex and the inferior colliculus. The cytoarchitecture and neurochemistry of the DCN is similar to that of the cerebellum, an important concept in theories of DCN function.Bell CC, Han V et al. Cerebellum-like structures and their implications for cerebellar function. Annu.Rev.Neurosci. 2008.Vol31.

Anatomically, the afferent limb consists of the retina, the optic nerve, and the pretectal nucleus in the midbrain, at level of superior colliculus. Ganglion cells of the retina project fibers through the optic nerve to the ipsilateral pretectal nucleus. The efferent limb is the pupillary motor output from the pretectal nucleus to the ciliary sphincter muscle of the iris. The pretectal nucleus projects crossed and uncrossed fibers to the ipsilateral and contralateral Edinger-Westphal nuclei, which are also located in the midbrain.

Again, depending on the stress and strain the muscles sustains, this afferent and efferent coordination will measure the "stretch of the spring" and communicate the results to the central nervous system. A similar structure attaching one end to muscle and the other end to a tendon is known as a Golgi tendon organ. However, Golgi tendon organs differ from nuclear chain and nuclear bag fibers in that they are considered in series rather than in parallel to the muscle fibers.

The nucleus raphe obscurus, despite the implications of its name, has some very specific functions and connections of afferent and efferent nature. The nucleus raphes obscurus projects to the cerebellar lobes VI and VII and to crus II along with the nucleus raphe pontis. The nucleus raphes obscurus has also been implicated in the modulation of the hypoglossal nerve. It has been observed that the ablation of this nucleus causes a change in the firing pattern of this cranial nerve.

Via the rete testis, the seminiferous tubules become connected with outgrowths from the mesonephros, which form the efferent ducts of the testis. The descent of the testes consists of the opening of a connection from the testis to its final location at the anterior abdominal wall, followed by the development of the gubernaculum, which subsequently pulls and translocates the testis down into the developing scrotum. Ultimately, the passageway closes behind the testis. A failure in this process causes an indirect inguinal hernia.

During the midfetal period of fetal development the subplate zone is the largest zone in the developing telencephalon. It serves as a waiting compartment for growing cortical afferents; its cells are involved in the establishment of pioneering cortical efferent projections and transient fetal circuitry, and apparently have a number of other developmental roles. The subplate zone is a phylogenetically recent structure and it is most developed in the human brain. Subplate neurons (SPNs) are among the first generated neurons in the mammalian cerebral cortex .

The vagus nerve is a primary component of the autonomic nervous system. The polyvagal theory focuses on the structure and function of the two efferent branches of the vagus, both of which originate in the medulla. More specifically, each branch is claimed to be associated with a different adaptive behavioural strategy, both of which are inhibitory in nature, being part of the parasympathetic nervous system. The vagal system is claimed to be in opposition to the sympathetic-adrenal system, which is involved in mobilization behaviours.

The testes are covered by a tough membranous shell called the tunica albuginea. Within the testes are very fine coiled tubes called seminiferous tubules. The tubules are lined with a layer of cells (germ cells) that develop from puberty through old age into sperm cells (also known as spermatozoa or male gametes). The developing sperm travel through the seminiferous tubules to the rete testis located in the mediastinum testis, to the efferent ducts, and then to the epididymis where newly created sperm cells mature (see spermatogenesis).

The efferent pathways include the cerebellorubral, dentatothalamic, and fastigioreticular tracts. All of them emerge from cerebellar nuclei; the cerebellorubral fibers from the globose and emboliform nuclei, the dentatothalamic fibers from the dentate nucleus, and the fastigioreticular fibers from the fastigial nucleus. They emerge together from the various nuclei to ascend in the roof of the fourth ventricle and proceed anteriorly to the midbrain tegmental area medial to the lateral lemniscus. The cerebellorubral fibers cross over at this point to enter the contralateral red nucleus.

The extraglomerular mesangial cells are found between the afferent and efferent arterioles towards the vascular pole of the glomerulus. The extraglomerular mesangial cells are adjacent to the intraglomerular mesangial cells that are located inside the glomerulus and in between the capillaries. The primary function of mesangial cells is to remove trapped residues and aggregated protein from the basement membrane thus keeping the filter free of debris. The contractile properties of mesangial cells have been shown to be insignificant in changing the filtration pressure of the glomerulus.

Experiments have found that the temporal length of the motor control loop takes approximately 250-400 ms. Motor centers, however, are already making corrections to their previous motor plan about 70 ms after the onset of the movement based on peripheral information that should not have arrived yet. It is thus likely that there are motor emulators that receive and process efferent copies and then send predictive peripheral output before the actual peripheral output from sensors is received. Motor centers often have to run very quickly.

In 1986, Pellionisz described the geometrization of the "three-neuron vestibulo-ocular reflex arc" in a cat using tensor network theory. The "three-neuron vestibulo-ocular reflex arc" is named for the three neuron circuit the arc comprises. Sensory input into the vestibular system (angular acceleration of the head) is first received by the primary vestibular neurons which subsequently synapse onto secondary vestibular neurons. These secondary neurons carry out much of the signal processing and produce the efferent signal heading for the oculomotor neurons.

This video demonstrates a range in the severity of seizures which all fall into the five classical stages when a stimulus that causes seizures is added to the rat model. For example, rats can be seen rearing (standing on their hind legs) and falling over, which demonstrate the fourth and fifth Racine stages. As the intensity of the seizure increases, the severity efferent actions increase. Each stage is a result of the action potentials causing the muscle to contract and relax resulting in an involuntary, observable action.

Diagram showing the basic physiologic mechanisms of the kidney In renal physiology, ultrafiltration occurs at the barrier between the blood and the filtrate in the glomerular capsule (Bowman's capsule) in the kidneys. As in nonbiological examples of ultrafiltration, pressure (in this case blood pressure) and concentration gradients lead to a separation through a semipermeable membrane (provided by the podocytes). The Bowman's capsule contains a dense capillary network called the glomerulus. Blood flows into these capillaries through the afferent arterioles and leaves through the efferent arterioles.

Hereditary motor and sensory neuropathies (HMSN) is a name sometimes given to a group of different neuropathies which are all characterized by their impact upon both afferent and efferent neural communication. HMSN are characterised by atypical neural development and degradation of neural tissue. The two common forms of HMSN are either hypertrophic demyelinated nerves or complete atrophy of neural tissue. Hypertrophic condition causes neural stiffness and a demyelination of nerves in the peripheral nervous system, and atrophy causes the breakdown of axons and neural cell bodies.

It appears the function of the rete testis is to mix the sperm as they leave the seminiferous tubules. Sperm leave the seminiferous tubules in the dilute secretions of Sertoli cells. The rete testis does modify the luminal fluids with a limited amount of secretion and reabsorption, but their primary function is to mix and transport the sperm into the efferent ductules, where the major function is reabsorption of about 95% of the fluid, which increases the sperm concentration prior to entering the epididymis.

The autonomic nervous system can work with or without the control of the CNS (that's why it's called 'autonomous'), and also has two subdivisions, called sympathetic and parasympathetic, which are important for transmitting motor orders to the body's basic internal organs, thus controlling functions such as heartbeat, breathing, digestion, and salivation. Autonomic nerves, unlike somatic nerves, contain only efferent fibers. Sensory signals coming from the viscera course into the CNS through the somatic sensory nerves (e.g., visceral pain), or through some particular cranial nerves (e.g.

Striking of the patellar tendon with a reflex hammer just below the patella stretches the muscle spindle in the quadriceps muscle. This produces a signal which travels back to the spinal cord and synapses (without interneurons) at the level of L3 in the spinal cord, completely independent of higher centres. From there, an alpha motor neuron conducts an efferent impulse back to the quadriceps femoris muscle, triggering contraction. This contraction, coordinated with the relaxation of the antagonistic flexor hamstring muscle causes the leg to kick.

This is a relative contraindication to surgery. The appendix is also used for the construction of an efferent urinary conduit, in an operation known as the Mitrofanoff procedure, in people with a neurogenic bladder. The appendix is also used as a means to access the colon in children with paralysed bowels or major rectal sphincter problems. The appendix is brought out to the skin surface and the child/parent can then attach a catheter and easily wash out the colon (via normal defaecation) using an appropriate solution.

As is the case with many concepts found in engineering, automatic gain control is also found in biological systems, especially sensory systems. For example, in the vertebrate visual system, calcium dynamics in the retinal photoreceptors adjust gain to suit light levels. Further on in the visual system, cells in V1 are thought to mutually inhibit, causing normalization of responses to contrast, a form of automatic gain control. Similarly, in the auditory system, the olivocochlear efferent neurons are part of a biomechanical gain control loop.

Classified as a sensory circumventricular organ (along with the SFO and AP), the vascular organ of lamina terminalis (VOLT) is situated in the anterior wall of the third ventricle. Characteristically of the CVOs, it lacks the tight endothelial blood brain barrier. The vascular organ is further characterized by the afferent inputs from the subfornical organ (SFO), the median pre-optic nucleus (MnPO) region, the brainstem, and even the hypothalamus. Conversely, the vascular organ of the lamina terminalis maintains efferent projections to the stria medullaris and basal ganglia.

The celiac ganglion is part of the sympathetic prevertebral chain possessing a great variety of specific receptors and neurotransmitters such as catecholamines, neuropeptides, and nitric oxide and constitutes a modulation center in the pathway of the afferent and efferent fibers between the central nervous system and the ovary. The main preganglion neurotransmitter of the celiac ganglion is acetylcholine, yet the celiac ganglion-mesenteric complex also contain α and β adrenergic receptors and is innervated by fibers of adrenergic nature that come from other preaortic ganglia.

In the human brain, the superior cerebellar peduncle (brachium conjunctivum) is a paired structure of white matter that connects the cerebellum to the midbrain. It consists mainly of efferent fibers, the cerebellothalamic tract that runs from a cerebellar hemisphere to the contralateral thalamus, and the cerebellorubral tract that runs from a cerebellar hemisphere to the red nucleus. It also contains afferent tracts, most prominent of which is the ventral spinocerebellar tract. Other afferent tracts are the trigeminothalamic fibers, tectocerebellar fibers, and noradrenergic fibers from the locus coeruleus.

The central nervous system controls muscle spindle sensitivity via the fusimotor system. It consists of muscle spindles along with fusimotor neurons - beta motor neurons and gamma motor neurons. Because beta motor neurons innervate extrafusal as well as intrafusal muscle fibers, they are more specifically named skeletofusimotor neurons. Gamma motor neurons are the efferent (sending signals away from the central nervous system) part of the fusimotor system, whereas muscle spindles are the afferent part, as they send signals relaying information from muscles toward the spinal cord and brain.

The optic nerve, or more precisely, the photosensitive ganglion cells through the retinohypothalamic tract, is responsible for the afferent limb of the pupillary reflex; it senses the incoming light. The oculomotor nerve is responsible for the efferent limb of the pupillary reflex; it drives the iris muscles that constrict the pupil. Pathways in the Ciliary ganglion. #Retina: The pupillary reflex pathway begins with the photosensitive retinal ganglion cells, which convey information via the optic nerve, the most peripheral, distal, portion of which is the optic disc.

If the kidney is methodologically perfused at moderate pressures (90–220 mm Hg performed on an experimental animal; in this case, a dog), then, there is a proportionate increase of: -Renal Vascular Resistance Along with the increase in pressure. At low perfusion pressures, Angiotensin II may act by constricting the efferent arterioles, thus mainlining the GFR and playing a role in autoregulation of Renal Blood Flow. People with poor blood flow to the kidneys caused by medications that inhibit angiotensin-converting enzyme may face kidney failure.

The periaqueductal grey matter, an area of the brain involved in mediating analgesia, sends efferent connections to the nucleus raphe magnus when it is stimulated by opiates (endogenous or otherwise). Electrical stimulation of the PAG produces analgesia, as well as administration of morphine to the PAG or nucleus raphe magnus. The antinociceptic effects of electrical stimulation of the PAG can be blocked by administering naloxone, an opiate antagonist, to the nucleus raphe magnus. Similarly, afferent fibres from the spinothalamic tract synapse at the periaqueductal grey matter.

In the male frog, the two testes are attached to the kidneys and semen passes into the kidneys through fine tubes called efferent ducts. It then travels on through the ureters, which are consequently known as urinogenital ducts. There is no penis, and sperm is ejected from the cloaca directly onto the eggs as the female lays them. The ovaries of the female frog are beside the kidneys and the eggs pass down a pair of oviducts and through the cloaca to the exterior.

The subthalamic nucleus essentially provides the excitement needed to drive the globus pallidus. Injury to this area or its efferent or afferent connections can induce this disorder contralateral to the side of the lesion. The structure itself is a regulator of motor function and is also involved in associative and limbic functions. It was traditionally thought that the disorder was only caused by injury to the subthalamic nucleus, but later studies have shown that damage to other basal ganglia regions can also be responsible for causing this disorder.

If true, this method could be useful to measure individual differences in stress reactivity. RSA is the widely used measure of the amplitude of heart rate rhythm associated with rate of spontaneous breathing. Research has shown that amplitude of RSA is an accurate indicator of the efferent influence of the vagus on the heart. Since inhibitory effects of the VVC branch of the vagus allow for a wide range of adaptive, prosocial behaviors, it has been theorized that individuals with greater vagal tone are able to exhibit a greater range of such behaviors.

This gene is a member of the ligand-gated ionic channel family and nicotinic acetylcholine receptor gene superfamily. It encodes a plasma membrane protein that forms homo- or hetero-oligomeric divalent cation channels. This protein is involved in cochlea hair cell function and is expressed in both the inner and outer hair cells (OHCs) of the adult cochlea, although expression levels in adult inner hair cells is low. The activation of the alpha9/10 nAChR is via olivocochlear activity, represented by cholinergic efferent synaptic terminals originating from the superior olive region of the brainstem.

Animation of the migration of spermatozoa from their origin as germ cells to their exit from the vas deferens. A.) Blood vessels; B.) Head of epididymis; C.) Efferent ductules; D.) Seminiferous tubules; E.) Parietal lamina of tunica vaginalis; F.) Visceral lamina of tunica vaginalis; G.) Cavity of tunica vaginalis; H.) Tunica albuginea; I.) Lobule of testis; J.) Tail of epididymis; K.) Body of epididymis; L.) Mediastinum; M.) Vas deferens. Testicle or testis (plural testes) is the male reproductive gland or gonad in all animals, including humans. It is homologous to the female ovary.

All of these sinuses drain into the efferent lymphatic vessels to exit the node at the hilum on the concave side. These are channels within the node lined by endothelial cells along with fibroblastic reticular cells, allowing for the smooth flow of lymph. The endothelium of the subcapsular sinus is continuous with that of the afferent lymph vessel and also with that of the similar sinuses flanking the trabeculae and within the cortex. These vessels are smaller and don't allow the passage of macrophages so that they remain contained to function within a lymph node.

The medial vestibulospinal tract is a group of descending extrapyramidal motor neurons, or efferent fibers found in the anterior funiculus, a bundle of nerve roots in the spinal cord. The medial vestibulospinal tract originates in the medial vestibular nucleus or Schwalbe's nucleus. The Schwalbe's nucleus extends from the rostral end of the inferior olivary nucleus of the medulla oblongata to the caudal portion of the pons. Medial vestibulospinal fibers join with the ipsilateral and contralateral medial longitudinal fasciculus, and descend in the anterior funiculus of the spinal cord.

The efferent arterioles of the juxtamedullary glomeruli are much different. They do break up, but they form bundles of vessels (arteriolae recti) that cross the outer zone of the medulla to perfuse the inner zone. Vessels returning from the inner medulla (venulae recti) intersperse themselves in a highly regular fashion among the descending arteriolae recti to form a well- organized rete mirabile. This rete is responsible for the osmotic isolation of the inner medulla from the rest of the kidney and so permits the excretion of a hypertonic urine when circumstances require.

The juxtaglomerular cells (JG cells, or granular cells) are cells in the kidney that synthesize, store, and secrete the enzyme renin. They are specialized smooth muscle cells mainly in the walls of the afferent arterioles (and some in the efferent arterioles) that deliver blood to the glomerulus. In synthesizing renin, they play a critical role in the renin–angiotensin system and thus in autoregulation of the kidney. Juxtaglomerular cells secrete renin in response to a drop in pressure detected by stretch receptors in the vascular walls, or when stimulated by macula densa cells.

A motor program is an abstract representation of movement that centrally organizes and controls the many degrees of freedom involved in performing an action.p. 182 Signals transmitted through efferent and afferent pathways allow the central nervous system to anticipate, plan or guide movement. Evidence for the concept of motor programs include the following:p. 182 :# Processing of afferent information (feedback) is too slow for on-going regulation of rapid movements. :# Reaction time (time between “go” signal and movement initiation) increases with movement complexity, suggesting that movements are planned in advance.

Mesangial cells have irregular shapes with flattened-cylinder-like cell bodies and processes at both ends containing actin, myosin and actinin, giving mesangial cells contractile properties. The anchoring filaments from mesangial cells to the glomerular basement membrane can alter capillary flow by changing glomerular ultrafiltration surface area. Extraglomerular mesangial cells are in close connection to afferent and efferent arteriolar cells by gap junctions, allowing for intercellular communication. Mesangial cells are separated by intercellular spaces containing extracellular matrix called the mesangial matrix that is produced by the mesangial cells.

Within the cortex, nephrons are organized around central veins of the efferent venous system. In contrast, the medulla is structured into medullary cones that contain nephron elements, specifically collecting ducts and loops of Henle. As the collecting ducts descend through the medulla, they combine and empty their contents into the ureter. There are two types of avian nephrons, and nephrons become larger as depth from the kidney surface increases. Reptilian-type nephrons are the smallest nephrons, are found near a kidney’s surface, possess simple glomeruli, and do not have loops of Henle.

The molecular basis of cytokine-inhibiting signals requires the neurotransmitter acetylcholine, and the Alpha-7 nicotinic receptor receptor expressed on cytokine-producing cells. The release of acetylcholine in spleen suppresses the production of TNF and other cytokines which cause damaging inflammation. Signaling in the efferent arc of the inflammatory reflex, termed the "Cholinergic anti-inflammatory pathway," provides a regulatory check on the innate immune system response to invasion and injury. The action potentials arising in the vagus nerve are transmitted to the spleen, where a subset of specialized T cells is activated to secrete acetylcholine.

De Graaf's position in the history of reproduction is unique, summarising the work of anatomists before his time, but unable to benefit from the advances about to be made by microscopy, although he reported its use by Antonie van Leeuwenhoek in 1673. His personal contributions include the description of testicular tubules, the efferent ducts, and corpora lutea. De Graaf may have been the first to understand the reproductive function of the Fallopian tube, described the hydrosalpinx, linking its development to female infertility. De Graaf also invented a practical syringe, described in his third treatise.

They also receive input from efferent nerve fibers leading back to the same set of nerves. The entire cluster of cells is infiltrated with capillaries to provide access to the bloodstream; the high capillary density makes this one of the areas of the body with the greatest blood flow. Type I cells are densely packed with vesicles containing various neurotransmitters, including dopamine, ATP, serotonin, catecholamine, released during transduction. Type I cells are often connected via gap junctions, which might allow for quick communication between cells when transducing signals.

Renal sympathetic denervation (RSDN), is a minimally invasive, endovascular catheter based procedure using radiofrequency ablation or ultrasound ablation aimed at treating resistant hypertension (high blood pressure not controlled by medication). Nerves in the wall of the renal artery are ablated by applying radiofrequency pulses or ultrasound to the renal arteries. This causes reduction of sympathetic afferent and efferent activity to the kidney and blood pressure can be decreased. Early data from international clinical trials without sham controls was promising - demonstrating large blood pressure reductions in patients with treatment-resistant hypertension.

The results showed a significant decrease in intracortical inhibition, which resulted in a slowdown of interstimulus intervals by 3 ms. In addition to its proximity to and association with the limbic system and the amygdala in particular, which plays a key role in emotional experience, the anterior cingulate cortex shares afferent and efferent pathways with a number of thalamic nuclei as well as the posterior cingulate and part of some parietal, frontal and supplementary motor cortex.Cohen et al. (1999). Alteration of Intention and Self-Initiated Action Associated With Bilateral Anterior Cingulotomy.

With regard to fiber diameter there are two main categories: A-fibers are large and conduct impulses at high or moderate speed (5–75 m/s). C-fibers are small and conduct impulses at low speed (around 1 m/s). In microneurography recordings, A- and C-fiber impulses differ in shape. Because fibers are mixed in most nerves, it is usually essential to record from an individual nerve fiber at a time to explore the properties of a functional system, although multi-unit recording has been very rewarding in studies of sympathetic efferent activity.

Agrammatism was first coined by Adolf Kussmaul in 1887 to explain the inability to form words grammatically and to syntactically order them into a sentence. Later on, Harold Goodglass defined the term as the omission of connective words, auxiliaries and inflectional morphemes, all of these generating a speech production with extremely rudimentary grammar. Agrammatism, today seen as a symptom of the Broca's syndrome (Tesak & Code, 2008), has been also referred as 'motor aphasia' (Goldstein, 1948), 'syntactic aphasia' (Wepman & Jones, 1964), 'efferent motor aphasia' (Luria, 1970), and 'non-fluent aphasia' (Goodglass et al., 1964).

" Instead, the focus of her thinking throughout her long career was on how individuals came to negotiate their readings in social terms. Such an ongoing conversation between reader(s) and text(s) was her way of emphasizing the importance of literature for human development in democratic settings.See for instance, Gordon M. Pradl, Literature for Democracy: Reading As a Social Act, Chapters 9 & 10. As part of her "transactional" theory, Rosenblatt distinguished between two kinds of reading, or "stances," which she viewed on a continuum between "efferent" and "aesthetic.

Reflex arc demonstrated When a reflex arc in an animal consists of only one sensory neuron and one motor neuron, it is defined as monosynaptic, referring to the presence of a single chemical synapse. In the case of peripheral muscle reflexes (patellar reflex, achilles reflex), brief stimulation to the muscle spindle results in contraction of the agonist or effector muscle. By contrast, in polysynaptic reflex pathways, one or more interneurons connect afferent (sensory) and efferent (motor) signals. All but the most simple reflexes are polysynaptic, allowing processing or inhibition of polysynaptic reflexes within the brain.

They are crucial participants in a corollary discharge system designed to limit self-generated interference. When a fish moves, it creates disturbances in the water that could be detected by the lateral line system, potentially interfering with the detection of other biologically relevant signals. To prevent this, an efferent signal is sent to the hair cell upon motor action, resulting in inhibition which counteracts the excitation resulting from reception of the self-generated stimulation. This allows the fish to retain perception of motion stimuli without interference created by its own movements.

Diphenidol is a muscarinic antagonist employed as an antiemetic and as an antivertigo agent. It is not marketed in the United States or Canada. Although the mechanism of action of diphenidol on the vestibular system has not yet been elucidated, it exerts an anticholinergic effect due to interactions with mACh receptors, particularly M1, M2, M3 and M4. Hence, its actions may take place at the vestibular nuclei, where a significant excitatory input is mediated by ACh receptors, and also at the vestibular periphery where mACh receptors are expressed at efferent synapses.

The ghrelin receptor GHS-R1a (a splice-variant of the growth hormone secretagogue receptor, with the GHS-R1b splice being inactive) is involved in mediating a wide variety of biological effects of ghrelin, including: stimulation of growth hormone release, increase in hunger, modulation of glucose and lipid metabolism, regulation of gastrointestinal motility and secretion, protection of neuronal and cardiovascular cells, and regulation of immune function. They are present in high density in the hypothalamus and pituitary, on the vagus nerve (on both afferent cell bodies and efferent nerve endings) and throughout the gastrointestinal tract.

Initially, there is constriction of the efferent arterioles and dilation of afferent arterioles, with resulting glomerular capillary hypertension and hyperfiltration; this gradually changes to hypofiltration over time. Concurrently, there are changes within the glomerulus itself: these include a thickening of the basement membrane, a widening of the slit membranes of the podocytes, an increase in the number of mesangial cells, and an increase in mesangial matrix. This matrix invades the glomerular capillaries and produces deposits called Kimmelstiel-Wilson nodules. The mesangial cells and matrix can progressively expand and consume the entire glomerulus, shutting off filtration.

When there is a discrepancy between these two signals, the cerebellum determines the appropriate correction and relays this information to the brainstem and motor cortex. Cerebellar output to the brainstem is thought to be specifically related to postural muscle tone while output to the motor cortex is related to cognitive and motor programming processes. The cerebellum sends signals to the cerebral cortex and the brain stem in response to sensory signals received from the spinal cord. Efferent signals from these regions go to the spinal cord where motor neurons are activated to regulate gait.

When the afferent and efferent nerves are both destroyed, as they may be by tumors of the cauda equina or filum terminale, the bladder is flaccid and distended for a while. Gradually, however, the muscle of the "decentralized bladder" becomes active, with many contraction waves that expel dribbles of urine out of the urethra. The bladder becomes shrunken and the bladder wall hypertrophied. The reason for the difference between the small, hypertrophic bladder seen in this condition and the distended, hypotonic bladder seen when only the afferent nerves are interrupted is not known.

In the male the duct persists, and forms the tube of the epididymis, the vas deferens and the ejaculatory duct, while the seminal vesicle arises during the third month as a lateral diverticulum from its hinder end. A large part of the head end of the mesonephros atrophies and disappears; of the remainder the anterior tubules form the efferent ducts of the testicle; while the posterior tubules are represented by the ductuli aberrantes, and by the paradidymis, which is sometimes found in front of the spermatic cord above the head of the epididymis.

The inferior salivatory nucleus (or nucleus salivatorius inferior) is a cluster of neurons in the pontine tegmentum (dorsal part of the pons), just above its junction with the medulla. It is the general visceral efferent (GVE) component of the glossopharyngeal nerve supplying the parasympathetic input to the parotid gland for salivation. It lies immediately caudal to the superior salivatory nucleus and just above the upper end of the dorsal nucleus of the vagus nerve in the medulla. The preganglionic parasympathetic fibres originate in the inferior salivatory nucleus of the glossopharyngeal nerve.

This network of pathways "releases a short pulse of dopamine onto many dendrites, thus broadcasting a global reinforcement signal to postsynaptic neurons." This allows recently activated synapses to increase their sensitivity to efferent (conducting outward) signals, thus increasing the probability of occurrence for the recent responses that preceded the reinforcement. These responses are, statistically, the most likely to have been the behavior responsible for successfully achieving reinforcement. But when the application of reinforcement is either less immediate or less contingent (less consistent), the ability of dopamine to act upon the appropriate synapses is reduced.

The tubules are lined with a layer of cells (germ cells) that from puberty into old age, develop into sperm cells (also known as spermatozoa or male gametes). The developing sperm travel through the seminiferous tubules to the rete testis located in the mediastinum testis, to the efferent ducts, and then to the epididymis where newly created sperm cells mature (see spermatogenesis). The sperm move into the vas deferens, and are eventually expelled through the urethra and out of the urethral orifice through muscular contractions. However, most fish do not possess seminiferous tubules.

Increased blood volume results in increased venous return to the heart, which leads to increased firing of B-fibers. B-fibers send signals to the brain (the afferent pathway of the neural portion of the Bainbridge reflex), which then modulates both sympathetic and parasympathetic pathways to the SA node of the heart (the efferent pathway of the neural portion of the Bainbridge reflex), causing an increase in heart rate. "Effects on cardiac contractility and stroke volume are insignificant." Bainbridge reflex can be blocked by atropine and can be abolished by cutting the vagus nerve.

The second Kedem–Katchalsky equation explains the trans endothelial transport of solutes, J_s . Glomerular capillaries have a continuous glycocalyx layer in health and the total transendothelial filtration rate of solvent ( J_v ) to the renal tubules is normally around 125 ml/ min (about 180 litres/ day). Glomerular capillary J_v is more familiarly known as the glomerular filtration rate (GFR). In the rest of the body's capillaries, J_v is typically 5 ml/ min (around 8 litres/ day), and the fluid is returned to the circulation via afferent and efferent lymphatics.

Sperm are produced in the male sex gland or testicle. From there they travel through tubes (efferent tubules), exit the testes and enter a “storage site” or epididymis. The epididymis is a single, , tightly coiled, small tube, within which sperm mature to the point where they can move, swim and fertilize eggs. Testicular sperm are not able to fertilize eggs naturally (but can if they are injected directly into the egg in the laboratory), as the ability to fertilize eggs is developed slowly over several months of storage in the epididymis.

For the student described above, this may occur as he decides that he wishes to check the clock at the front of the classroom. #The muscles of the eye contract and it begins to quickly move towards the second object of interest through an action known as a saccade. As soon as this saccade begins, a signal is sent from the eye back to the brain. This signal, known as an efferent cortical trigger or efference copy, communicates to the brain that a saccade is about to begin.

The macula densa is a collection of densely packed epithelial cells at the junction of the thick ascending limb (TAL) and distal convoluted tubule (DCT). As the TAL ascends through the renal cortex, it encounters its own glomerulus, bringing the macula densa to rest at the angle between the afferent and efferent arterioles. The macula densa's position enables it to rapidly alter afferent arteriolar resistance in response to changes in the flow rate through the distal nephron. The macula densa uses the composition of the tubular fluid as an indicator of GFR.

When the cell swells, ATP escapes through a basolateral, stretch-activated, non-selective Maxi-Anion channel. The ATP is subsequently converted to adenosine by ecto-5′-nucleotidase. # Adenosine constricts the afferent arteriole by binding with high affinity to the A1 receptors a Gi/Go. Adenosine binds with much lower affinity to A2A and A2B receptors causing dilation of efferent arterioles. #The binding of adenosine to the A1 receptor causes a complex signal cascade involving the Gi subunit deactivating Ac, thus reducing cAMP and the Go subunit activating PLC, IP3 and DAG.

The peripheral nervous system is composed of afferent and efferent neurons; disorder of these neurons is called peripheral neuropathy. Vibration examination can detect and localize disorders of the peripheral nervous system. A gradual loss of sensation from the toes to the knees is consistent with a peripheral nerve problem, whereas an impairment in perceiving vibration from all extremities is a sign of a posterior column disorder. Impairments classified to the peripheral nervous system and posterior column are indicators of demyelination of afferent neurons from a variety of causes.

They are static, whereas the nuclear bag fibers are dynamic in comparison. The name "nuclear chain" refers to the structure of the central region of the fiber, where the sensory axons wrap around the intrafusal fibers. The secondary nerve association involves an efferent and afferent pathway that measure the stress and strain placed on the muscle (usually the extrafusal fibers connected from the muscle portion to a bone). The afferent pathway resembles a spring wrapping around the nuclear chain fiber and connecting to one of its ends away from the bone.

2018 As an example of a spinal reflex, it results in a fast response that involves an afferent signal into the spinal cord and an efferent signal out to the muscle. The stretch reflex can be a monosynaptic reflex which provides automatic regulation of skeletal muscle length, whereby the signal entering the spinal cord arises from a change in muscle length or velocity. It can also include a polysynaptic component, as in the tonic stretch reflex. When a muscle lengthens, the muscle spindle is stretched and its nerve activity increases.

Those diagnosed with autism tend to have many difficulties processing auditory stimuli. For example, they most often endure language and speech delays, hyperacusis, have difficulties communicating in large social groups, and may experience difficulties hearing certain voices in a noisy environment. These qualities make quality of life difficult, by inhibiting their ability to fully participate in social and educational circumstances in various parts of their lives. As shown in research published in the International Journal of Psychophysiology, efferent pathways throughout the brain help to control various functions throughout the body.

The sensory function of the trigeminal nerve is to provide tactile, proprioceptive, and nociceptive afference to the face and mouth. Its motor function activates the muscles of mastication, the tensor tympani, tensor veli palatini, mylohyoid and the anterior belly of the digastric. The trigeminal nerve carries general somatic afferent fibers (GSA), which innervate the skin of the face via ophthalmic (V1), maxillary (V2) and mandibular (V3) divisions. The trigeminal nerve also carries special visceral efferent (SVE) axons, which innervate the muscles of mastication via the mandibular (V3) division.

During development, semaphorins and their receptors may be involved in the sorting of pools of motor neurons and the modulation of pathfinding for afferent and efferent axons from and to these pools. For instance, Sema3a repels axons from the dorsal root ganglia, facial nerves, vagal nerves, olfactory-sensory, cortical nerves, hippocampal nerves and cerebellar nerves. Class 3 semaphorins have an important function after traumatic central nervous system injuries, such as spinal cord injury. They regulate neuronal and non-neuronal cells associated with the traumatic injury due to their presence in the scar tissue.

While the criticism does not address the clinical speculations of the polyvagal theory directly, it contradicts its premises. In particular, it undermines the suggestion that there is a phylogenetic hierarchy, where one vagal system is more primitive than the other, and therefore is activated only when the more evolved one fails (as in dissociation, or acute trauma). It has been known for roughly a century that "a differentiation of the visceral efferent column of the vagus nerve into a dorsal motor nucleus and a ventrolateral nucleus (nucleus ambiguus) is first seen in reptiles (Ariens Kappers, '12; Ariens Kappers et al., '36; Addens, '33)".

The efferent leg of the peripheral nervous system is responsible for conveying commands to the muscles and glands, and is ultimately responsible for voluntary movement. Nerves move muscles in response to voluntary and autonomic (involuntary) signals from the brain. Deep muscles, superficial muscles, muscles of the face and internal muscles all correspond with dedicated regions in the primary motor cortex of the brain, directly anterior to the central sulcus that divides the frontal and parietal lobes. In addition, muscles react to reflexive nerve stimuli that do not always send signals all the way to the brain.

The efferent motor neurons on the other hand adapted to the new situation and crossed. Like that the visual input on one side still controls the corresponding side of the body and hence the motor control on that side. So the right hemisphere controls the left part of the body and vice versa, which has in addition the advantage that the motor control and self defense can be maintained after injury on the injured side. It would make sense that the same mechanism also leads to the change from a convex to a concave retina, at least at the beginning of eye evolution.

Targeted reinnervation has an efferent and an afferent component. Targeted muscle reinnervation is a method by which a spare muscle (the target muscle) of an amputated patient is denervated (its original nerves cut and/or de-activated), then reinnervated with residual nerves of the amputated limb. The resultant EMG signals of the targeted muscle now represent the motor commands to the missing limb, and are used to drive a motorized prosthetic device. Targeted sensory reinnervation is a method by which skin near or over the targeted muscle is denervated, then reinnervated with afferent fibers of the remaining hand nerves.

Following the work of Robert Whytt and Marshall Hall, Laycock studied the reflex arc in relation to the nervous system. While Hall believed that the reflex arc was mediated by the spinal cord, separate from the cerebrum, Laycock argued that the brain underwent the same reflex patterns as the rest of the nervous system. After learning the German language, he translated books by Johann August Unzer, who studied afferent and efferent reflexes. Unzer centralised the nervous system in the spinal cord, such that reflexes could occur even without a functional brain, which only controls conscious activity.

The interposed nucleus is smaller than the dentate nucleus but larger than the fastigial nucleus and functions to modulate muscle stretch reflexes of distal musculature. It is located dorsal to the fourth ventricle and lateral to the fastigial nucleus; it receives afferent neuronal supply from the anterior lobe of the cerebellum and sends output via the superior cerebellar peduncle and the red nucleus. The fastigial nucleus is the most medial efferent cerebellar nucleus, targeting the pontine and medullary reticular formation as well as the vestibular nuclei. This region deals with antigravity muscle groups and other synergies involved with standing and walking.

In hypertension only the afferent arteriole is affected, while in diabetes mellitus, both the afferent and efferent arteriole are affected. ;Cause Lesions reflect leakage of plasma components across vascular endothelium and excessive extracellular matrix production by smooth muscle cells, usually secondary to hypertension. Hyaline arteriolosclerosis is a major morphologic characteristic of benign nephrosclerosis, in which the arteriolar narrowing causes diffuse impairment of renal blood supply, with loss of nephrons. The narrowing of the lumen can decrease renal blood flow and hence glomerular filtration rate leading to increased renin secretion and a perpetuating cycle with increasing blood pressure and decreasing kidney function.

In the distal 1/3 of the transverse colon, and through the sigmoid and rectum, and the cervix in females, the pelvic splanchnic nerves supply parasympathetic function, including transmitting the sensation of pain. The proximal 2/3 of the transverse colon, and the rest of the proximal gastrointestinal tract is supplied its parasympathetic fibers by the vagus nerve. The parasympathetic nervous system is referred to as the craniosacral outflow; the pelvic splanchnic nerves are the sacral component. They are in the same region as the sacral splanchnic nerves, which arise from the sympathetic trunk and provide sympathetic efferent fibers.

Upon application of pressure to the internal end of the cervix, oxytocin is released (therefore increase in contractile proteins), which stimulates uterine contractions, which in turn increases pressure on the cervix (thereby increasing oxytocin release, etc.), until the baby is delivered. Sensory information regarding mechanical stretch of the cervix is carried in a sensory neuron, which synapses in the dorsal horn before ascending to the brain in the anterolateral columns (ipsilateral and contralateral routes). Via the median forebrain bundle, the efferent reaches the PVN and SON of the hypothalamus. The posterior pituitary releases oxytocin due to increased firing in the hypothalamo-hypophyseal tract.

At the point where the afferent arterioles enter the glomerulus and the efferent arteriole leaves it, the tubule of the nephron touches the arterioles of the glomerulus from which it arose. At this location, in the wall of the distal convoluted tubule, there is a modified region of tubular epithelium called the macula densa. Cells in the macula densa respond to changes in the sodium chloride levels in the distal tubule of the nephron via the tubuloglomerular feedback (TGF) loop. The macula densa's detection of elevated sodium chloride, which leads to an increase in GFR, is based on the concept of purinergic signaling.

Another option is to insert a small pellet of medication into the urethra, but this requires higher doses than injections and may not be as effective. Topical medications to dilate the blood vessels have been used, but are not very effective or well tolerated. Electrical stimulation of efferent nerves at the S2 level can be used to trigger an erection that lasts as long as the stimulation does. Surgical implants, either of flexible rods or inflatable tubes, are reserved for when other methods fail because of the potential for serious complications, which occur in as many as 10% of cases.

Working at the Department of Clinical Neurophysiology, Academic Hospital, Uppsala, they collected data resulting in the first complete papers representing three areas to become major fields of microneurography, i.e. afference from intra-muscular sense organs during voluntary contractions, response of cutaneous sense organs related to touch stimuli, and efferent sympathetic activity controlling the constriction state of human blood vessels. The microneurography approach of Hagbarth and Vallbo based on epoxy resin coated tungsten electrodes is now generally accepted whereas an alternative attempt using glass coated platina-iridium electrodes had obviously limited success as it yielded a single short note alone.

On the other hand, sympathetic activity in skin nerves is dependent on a number of other mechanisms because changes are easily evoked e.g. by arousal, emotions, and ambient temperature changes, which stimuli are not effective with efferents in muscle nerves. These and other findings demonstrate that sympathetic efferent activity is highly differentiated, as individual effectors are governed by their own control systems and specific reflexes. The amount of muscular sympathetic activity, measured as number of bursts per 100 heart beats, varies considerably between subjects but, on the other hand, it is highly reproducible over time within the individual subject.

The epididymis, which is a tube that connects a testicle to a vas deferens in the male reproductive system, evolved by retention of the mesonephric duct during regression and replacement of the mesonephros with the metanephric kidney. Similarly, during embryological involution of the paired mesonephric kidneys, each mesonephric duct is retained to become the epididymis, vas deferens, seminal vesicle and ejaculatory duct (Wolffian duct). In reptiles and birds both the testes and excurrent ducts (efferent ducts, epididymis, vas deferens) occur in an intra-abdominal location (testicond). Primitive mammals, such as the monotremes (prototheria), also are testicond.

Coughing is a mechanism of the body that is essential to normal physiological function of clearing the throat which involves a reflex of the afferent sensory limb, central processing centre of the brain and the efferent limb. In conjunction to the components of the body that are involved, sensory receptors are also used. These receptors include rapidly adapting receptors which respond to mechanical stimuli, slowly adapting receptors and nociceptors which respond to chemical stimuli such as hormones in the body. To start the reflex, the afferent impulses are transmitted to the medulla of the brain this involves the stimulus which is then interpreted.

A wide variety of electrode designs have been researched, tested, and manufactured. These electrodes lie on a spectrum varying in degrees of invasiveness. Research in this area seeks to address issues centered around peripheral nerve/tissue damage, access to efferent and afferent signals, and selective recording/stimulation of nerve tissue. Ideally peripheral nerve interfaces are optimally designed to interface with biological constraints of peripheral nerve fibers, match the mechanical and electrical properties of the surrounding tissue, biocompatible with minimal immune response, high sensor resolution, are minimally invasive, and chronically stable with low signal-to-noise ratios.

Vagovagal reflex refers to gastrointestinal tract reflex circuits where afferent and efferent fibers of the vagus nerve coordinate responses to gut stimuli via the dorsal vagal complex in the brain. The vagovagal reflex controls contraction of the gastrointestinal muscle layers in response to distension of the tract by food. This reflex also allows for the accommodation of large amounts of food in the gastrointestinal tracts. The vagus nerve, composed of both sensory afferents and parasympathetic efferents, carries signals from stretch receptors, osmoreceptors, and chemoreceptors to dorsal vagal complex where the signal may be further transmitted to autonomic centers in the medulla.

Using an immobilized fish to prevent extraneous stimulation, a metal ball was vibrated at different frequencies. Utilizing single cell measurements with a microelectrode, responses were recorded and used to construct tuning curves, which revealed frequency preferences and two main afferent nerve types. One variety is attuned to collect mechanoreceptive information about acceleration, responding to stimulation frequencies between 30–200 Hz. The other type is sensitive to velocity information and is most receptive to stimulation below <30 Hz. This suggests a more intricate model of reception than was previously considered. The efferent synapses to hair cells are inhibitory and utilize acetylcholine as a transmitter.

Roy A. Wise, Drug-activation of brain reward pathways, Drug and Alcohol Dependence 1998; 51 13–22. The neurotransmitter system that has been most-clearly identified with the habit-forming actions of drugs-of-abuse is the mesolimbic dopamine system, with its efferent targets in the nucleus accumbens and its local GABAergic afferents. The reward-relevant actions of amphetamine and cocaine are in the dopaminergic synapses of the nucleus accumbens and perhaps the medial prefrontal cortex. Rats also learn to lever- press for cocaine injections into the medial prefrontal cortex, which works by increasing dopamine turnover in the nucleus accumbens.

Hyperfiltration is one of the earliest features of DN. Several mechanisms have been proposed to cause hyperfiltration. One of these mechanisms is that as glomeruli becomes hypertrophied, filtration surface area initially increases. Another possible mechanism is that abnormal vascular control in diabetic nephropathy leads to a reduction in afferent glomerular arteriolar resistance and an increase in efferent glomerular arteriolar resistance, leading to a net increase in renal blood flow (RBF) and glomerular filtration rate (GFR). Glomerular hyperfiltration and an aberrant regulation of RAAS lead to increased intraglomerular pressure, causing stress on the endothelial cells, the mesangial cells and the podocytes.

The first person to propose the existence of efferent copies was the German physician and physicist Hermann von Helmholtz in the middle of the 19th century. He argued that the brain needed to create an efference copy for the motor commands that controlled eye muscles so as to aid the brain's determining the location of an object relative to the head. His argument used the experiment in which one gently presses on one's own eye. If this is done, one notices that the visual world seems to have "moved" as a result of this passive movement of the eyeball.

A command neuron is a single neuron (or small set of neurons) whose stimulation results in the evocation of an endogenous, specific, naturally occurring behavior pattern (Carew, 2000). Command neurons act as neural decision making cells; push buttons that can trigger a complete, coordinated behavioral act and are often the sole determinant of whether an action is performed or not. Command neurons receive a convergence of integrative and sensory input and output to a multifarious group of pattern generating efferent cells. Stimulation of the command neuron triggers a lower level central pattern generator whose motorneurons and interneurons produce a particular fixed action pattern.

The periphery of the testes are converted into the tunica albuginea. Cords of the central mass run together and form a network which becomes the rete testis, and another network, which develops the seminiferous tubules. Via the rete testis, the seminiferous tubules become connected with outgrowths from the mesonephros, which form the efferent ducts of the testis. In short, the descent of the testes consists of the opening of a connection from the testis to its final location at the anterior abdominal wall, followed by the development of the gubernaculum, which subsequently pulls and translocates the testis down into the developing scrotum.

Relatively little is known about the function of the area postrema in humans. However, there is strong evidence that the area postrema acts as the chemoreceptor trigger zone for vomiting, which is triggered by the presence of noxious stimulation from the blood. There is also evidence that the area postrema is the site at which angiotensin stimulates glucose metabolism, presumed efferent neural activity, blood pressure control, and thirst. The area postrema also has integrative capacities that enable it to send major and minor efferents to sections of the brain involved in the autonomic control of cardiovascular and respiratory activities.

Furthermore, JG cells contain beta-1 adrenergic receptors, and so activation of the sympathetic nervous system will further stimulate renin release. Thus, a drop in blood pressure results in preferential vasodilation of the afferent arterioles, increasing renal blood flow (RBF), renal plasma flow (RPF) and GFR due to greater blood flow to the glomerulus. Note that there is no change in filtration fraction, as both GFR and RPF are increased. It also results in the release of renin, which, through the renin–angiotensin system, causes constriction of the efferent arterioles, which ultimately increases hydrostatic pressure in the glomerulus.

The Langerhans cells, once they are activated, rapidly migrate to the lymph nodes where they will accumulate in the paracortex and show the antigen of the skin to the lymph nodes via efferent lymph vessels. The Langerhans cells induce a vast proliferation of the naïve lymphocytes T and they participate in the immunoestimulation phase of the immune response, converting the lymphocytes in T helper cells. Recently, it has been shown that Langerhans cells can express an antigenic peptide associated to MHC-I capable of inducing a response from the cytotoxic LT and effector functions, such as the production of cytokines.

Since both the short and long ciliary nerves carry the afferent limb of the corneal reflex, one can test the integrity of the nasociliary nerve (and, ultimately, the trigeminal nerve) by examining this reflex in the patient. Normally both eyes should blink when either cornea (not the conjunctiva, which is supplied by the adjacent cutaneous nerves) is irritated. If neither eye blinks, then either the ipsilateral nasociliary nerve is damaged, or the facial nerve (CN VII, which carries the efferent limb of this reflex) is bilaterally damaged. If only the contralateral eye blinks, then the ipsilateral facial nerve is damaged.

Michael Charles Liberman (July 17, 1950) was born to Alvin Liberman and Isabelle Liberman in Storrs, Connecticut. He is now Director of the Eaton- Peabody Laboratory at the Massachusetts Eye and Ear Infirmary in Boston, and Harold Schuknecht Professor of Otology and Laryngology and Health Sciences and Technology at Harvard Medical School. He is a past president of the Association for Research in Otolaryngology. His research is concerned with the physiology and anatomy of the auditory nerve and cochlear efferent innervation, as well as noise-induced cochlear pathology; he has published over 100 peer-reviewed papers in these areas.

A motor neuron (or motoneuron) is a neuron whose cell body is located in the motor cortex, brainstem or the spinal cord, and whose axon (fiber) projects to the spinal cord or outside of the spinal cord to directly or indirectly control effector organs, mainly muscles and glands. There are two types of motor neuron – upper motor neurons and lower motor neurons. Axons from upper motor neurons synapse onto interneurons in the spinal cord and occasionally directly onto lower motor neurons. The axons from the lower motor neurons are efferent nerve fibers that carry signals from the spinal cord to the effectors.

Muscle coordination, muscle memory, and innate game awareness all rely on the nervous system to produce a specific firing pattern in response to an either an efferent or afferent signal. Sports are governed by the same production and perception of oscillations that govern much of human activity. For example, in basketball, in order to anticipate the game one must recognize rhythmic patterns of other players and perform actions calibrated to these movements. "The rhythm of a game of basketball emerges from the rhythm of individuals, the rhythm among team members, and the rhythmic contrasts between opposing teams".

The neurophysiological mechanisms by which phantom limbs occur is still under debate. A common theory posits that the afferent neurons, since deafferented due to amputation, typically remap to adjacent cortical regions within the brain. This can cause amputees to report feeling their missing limb being touched when a seemingly unrelated part of the body is stimulated (such as if the face is touched, but the amputee also feels their missing arm being stroked in a specific location). Another facet of phantom limbs is that the efferent copy (motor feedback) responsible for reporting on position to the body schema does not attenuate quickly.

The most direct of related disorders, deafferentation occurs when sensory input from the body is reduced or absent, without affecting efferent, or motor, neurons. The most famous case of this disorder is "IW", who lost all sensory input from below the neck, resulting in temporary paralysis. He was forced to learn to control his movement all over again using only his conscious body image and visual feedback. As a result, when constant visual input is lost during an activity, such as walking, it becomes impossible for him to complete the task, which may result in falling, or simply stopping.

When the central nervous system sends out signals to alpha neurons to fire, signals are also sent to gamma motor neurons to do the same. This process maintains the tautness of muscle spindles and is called alpha gamma co-activation. The nuclei of spindle muscle cells are located in the middle of these spindles, but unlike extrafusal muscle fibers, the myofibril contractile apparati of spindle fibers are located only at both ends of spindle. Efferent stimulation of the spindle by gamma motor neurons contracts the myofibrils, tautening the central region of spindle -- which maintains the muscle spindle's sensitivity to muscle's length change.

At gestational weeks 19–23, PCD is observed in post-mitotic cells. The prevailing theory explaining this observation is the neurotrophic theory which states that PCD is required to optimize the connection between neurons and their afferent inputs and efferent targets. Another theory proposes that developmental PCD in the nervous system occurs in order to correct for errors in neurons that have migrated ectopically, innervated incorrect targets, or have axons that have gone awry during path finding. It is possible that PCD during the development of the nervous system serves different functions determined by the developmental stage, cell type, and even species.

Shortly after a spinal nerve exits the intervertebral foramen, it branches into the dorsal ramus, the ventral ramus, and the ramus communicans. Each of these three structures carries both sensory and motor information. Each spinal nerve carries both sensory and motor information, via efferent and afferent nerve fibers - ultimately via the motor cortex in the parietal cortex - but also through the phenomenon of reflex. Spinal nerves are referred to as “mixed nerves.” In the thoracic region they remain distinct from each other and each innervates a narrow strip of muscle and skin along the sides, chest, ribs, and abdominal wall.

Various types of brain-body interactions have been distinguished. For example, brain-gut interactions are biochemical signaling that takes place between the gastrointestinal tract and the central nervous system. Brain-heart interactions link cardiac physiology to activity in the central and peripheral nervous system and may explain how peripheral cardiovascular arousal can influence decision making and the regulation of social and emotional behaviours. Brain-muscle interactions involve both efferent nerve fibres that transmit action potentials to the muscles to generate muscle contractions and afferent nerve fibres that transmit somatosensory information back to the central nervous system.

The medial reticular formation and lateral reticular formation are two columns of nuclei with ill-defined boundaries that send projections through the medulla and into the midbrain. The nuclei can be differentiated by function, cell type, and projections of efferent or afferent nerves. Moving caudally from the rostral midbrain, at the site of the rostral pons and the midbrain, the medial RF becomes less prominent, and the lateral RF becomes more prominent. Existing on the sides of the medial reticular formation is its lateral cousin, which is particularly pronounced in the rostral medulla and caudal pons.

Corrugator supercilii muscle Because facial expressions involve both motor (efferent) and sensory (afferent) mechanisms, it is possible that effects attributed to facial feedback are due solely to feedback mechanisms, or feed- forward mechanisms, or some combination of both. Recently, strong experimental support for a facial feedback mechanism is provided through the use of botulinum toxin (commonly known as Botox) to temporarily paralyze facial muscles. Botox selectively blocks muscle feedback by blocking presynaptic acetylcholine receptors at the neuromuscular junction. Thus, while motor efference commands to the facial muscles remain intact, sensory afference from extrafusal muscle fibers, and possibly intrafusal muscle fibers, is diminished.

In this case, the signal from the afferent fiber does not reach the brain, but produces the reflexive movement by direct connections with the efferent nerves in the spine. However, the majority of muscle activity is volitional, and the result of complex interactions between various areas of the brain. Nerves that control skeletal muscles in mammals correspond with neuron groups along the primary motor cortex of the brain's cerebral cortex. Commands are routed through the basal ganglia and are modified by input from the cerebellum before being relayed through the pyramidal tract to the spinal cord and from there to the motor end plate at the muscles.

Gheorghe Marinescu and Anghel Radovici in their seminal 1920 paper hypothesized that both the afferent (receptive) and efferent (motor) arms of the reflex are on the same side (ipsilateral) to the hand stimulated; this hypothesis remains unsubstantiated. The PMR has been found to be present more frequently in various neurological conditions, both localized and diffuse. These include congenital conditions such as Down syndrome, where it is unclear whether the reflex persists throughout life, or disappears and then re-appears in association with the onset of Alzheimer disease pathology. The reflex is common in the elderly population and should not be taken as indicative of a dementing process.

Mayer waves are cyclic changes or waves in arterial blood pressure brought about by oscillations in baroreceptor and chemoreceptor reflex control systems. The waves are seen both in the ECG and in continuous blood pressure curves and have a frequency about 0.1 Hz (10-second waves). These waves were originally described by Siegmund Mayer, Ewald Hering and Ludwig Traube hence originally called "Traube–Hering–Mayer waves". Mayer waves can be defined as arterial blood pressure (AP) oscillations at frequencies slower than respiratory frequency and which show the strongest, significant coherence (strength of linear coupling between fluctuations of two variables in the frequency domain) with efferent sympathetic nervous activity (SNA).

The efferent component is a multidisciplinary team trained in early resuscitation interventions and advanced life support that rushes to the deteriorating patient’s bedside to prevent respiratory and cardiac arrest in order to improve the patient’s outcomes. Often called the medical emergency team (MET), rapid response team (RRT), critical care outreach team (CCOT), or rover team, the team responds to calls placed by clinicians or families at the bedside who have detected deterioration. It may also provide proactive outreach to patients at high risk for deterioration. Composition of the teams may vary but often include one critical care attending physician or fellow, at least one nurse, and a respiratory therapist.

The region includes the tegmentum, crus cerebri and pretectum. By this definition, the cerebral peduncles are also known as the basis pedunculi, while the large ventral bundle of efferent fibers is referred to as the cerebral crus or the pes pedunculi. The cerebral peduncles are located on either side of the midbrain and are the frontmost part of the midbrain, and act as the connectors between the rest of the midbrain and the thalamic nuclei and thus the cerebrum. As a whole, the cerebral peduncles assist in refining motor movements, learning of new motor skills, and converting proprioceptive information into balance and posture maintenance.

In the renal system, peritubular capillaries are tiny blood vessels, supplied by the efferent arteriole, that travel alongside nephrons allowing reabsorption and secretion between blood and the inner lumen of the nephron. Peritubular capillaries surround the cortical parts of the proximal and distal tubules, while the vasa recta go into the medulla to approach the loop of Henle. About one-fifth of the blood plasma is filtered as the blood passes through the glomerular capillaries; four-fifths continues into the peritubular capillaries. Ions and minerals that need to be saved in the body are reabsorbed into the peritubular capillaries through active transport, secondary active transport, or transcytosis.

The use of vagotomy to treat obesity is now being studied. The vagus nerve provides efferent nervous signals out from the hunger and satiety centers of the hypothalamus, a region of the brain central to the regulation of food intake and energy expenditure. The circuit begins with an area of the hypothalamus, the arcuate nucleus, that has outputs to the lateral hypothalamus (LH) and ventromedial hypothalamus (VMH), the brain's feeding and satiety centers, respectively. Animals with lesioned VMH will gain weight even in the face of severe restrictions imposed on their food intake, because they no longer provide the signaling needed to turn off energy storage and facilitate energy burning.

The neuromotor manifestation of the fencing response resembles reflexes initiated by vestibular stimuli. Vestibular stimuli activate primitive reflexes in human infants, such as the asymmetric tonic neck reflex, Moro reflex, and parachute reflex, which are likely mediated by vestibular nuclei in the brainstem. The lateral vestibular nucleus (LVN; Deiter’s nucleus) has descending efferent fibers in the vestibulocochlear nerve distributed to the motor nuclei of the anterior column and exerts an excitatory influence on ipsilateral limb extensor motoneurons while suppressing flexor motoneurons. The anatomical location of the LVN, adjacent to the cerebellar peduncles (see cerebellum), suggests that mechanical forces to the head may stretch the cerebellar peduncles and activate the LVN.

The vertebrate nervous system is divided into the central and peripheral nervous systems. The central nervous system (CNS) consists of the brain, retina, and spinal cord, while the peripheral nervous system (PNS) is made up of all the nerves and ganglia (packets of peripheral neurons) outside of the CNS that connect it to the rest of the body. The PNS is further subdivided into the somatic and autonomic nervous systems. The somatic nervous system is made up of "afferent" neurons, which bring sensory information from the somatic (body) sense organs to the CNS, and "efferent" neurons, which carry motor instructions out to the voluntary muscles of the body.

Structures such as the corona radiata, occipital-frontal fasciculus and uncinate fasciculus project to the claustrum from frontal, pericentral, parietal and occipital regions. Reciprocal connections also exist with motor, somatosensory, auditory and visual cortical regions. Altogether, these findings leave the claustrum as the most highly connected structure per regional volume in the brain and suggest that it may serve as a hub to coordinate activity of cerebral circuits. Interestingly, even with this extensive connectivity, most projections to and from the claustrum are ipsilateral (although there are still contralateral projections), and little evidence exists to describe its afferent or efferent connections with the brainstem and spinal cord.

Using acoustic stimuli to activate the MOC reflex pathway, recordings have been made from single efferent fibres in guinea pigs and cats. Both studies confirmed that MOC neurons are sharply tuned to frequency, as previously suggested by Cody and Johnstone (1982), and Robertson (1984). They also showed that the firing rate of MOC neurons increased as the intensity of sound increased from 0 to 100 dB SPL, and have comparable thresholds (within ~15 dB) to afferent neurons. Furthermore, both studies showed that most MOC neurons responded to sound presented in the ipsilateral ear, consistent with the majority of mammalian MOC neurons being contralaterally located.

If the actual sensory state matches the predicted one, self-agency is (likely to be) inferred. Indeed, the intentional binding effect (described above) may depend on the motor efference command; Engbert, Wohlschläger and Haggard (2008) provide data suggesting that compression of estimated intervals between action and effect occurs only for volitional actions initiated by the self and not for passive actions or for actions performed by others. These authors maintain an efferent motor command is necessary for a sense of agency. Indeed, omitting the effect of an action does eliminate intentional binding, so long as the probability of an effect given an action is sufficiently high (Moore and Haggard, 2008).

The pathophysiology of GvHD includes three phases: # The afferent phase: activation of APC (antigen presenting cells) # The efferent phase: activation, proliferation, differentiation and migration of effector cells # The effector phase: target tissue destruction Activation of APC occurs in the first stage of GvHD. Prior to haematopoietic stem cell transplantation, radiation or chemotherapy results in damage and activation of host tissues, especially intestinal mucosa. This allows the microbial products to enter and stimulate pro-inflammatory cytokines such as IL-1 and TNF-α. These proinflammatory cytokines increase the expression of MHC and adhesion molecules on APCs, thereby increasing the ability of APC to present antigen.

Next, the superior longitudinal muscle elevates the apex of the tongue to make contact with the hard palate and the bolus is propelled to the posterior portion of the oral cavity. Once the bolus reaches the palatoglossal arch of the oropharynx, the pharyngeal phase, which is reflex and involuntary, then begins. Receptors initiating this reflex are proprioceptive (afferent limb of reflex is IX and efferent limb is the pharyngeal plexus- IX and X). They are scattered over the base of the tongue, the palatoglossal and palatopharyngeal arches, the tonsillar fossa, uvula and posterior pharyngeal wall. Stimuli from the receptors of this phase then provoke the pharyngeal phase.

Enactive interfaces are new types of human-computer interface that express and transmit the enactive knowledge by integrating different sensory aspects. The driving concept of enactive interfaces is then the fundamental role of motor action for storing and acquiring knowledge (action driven interfaces). Enactive interfaces are then capable of conveying and understanding gestures of the user, in order to provide an adequate response in perceptual terms. Enactive interfaces can be considered a new step in the development of the human-computer interaction because they are characterized by a closed loop between the natural gestures of the user (efferent component of the system) and the perceptual modalities activated (afferent component).

The superior salivatory nucleus (or nucleus salivatorius superior) of the facial nerve is a visceromotor cranial nerve nucleus located in the pontine tegmentum. It is one of the salivatory nuclei. Parasympathetic efferent fibers of the facial nerve (preganglionic fibers) arise according to some authors from the small cells of the facial nucleus, or according to others from a special nucleus of cells scattered in the reticular formation, dorso-medial to the facial nucleus – the superior salivatory nucleus. Some of the preganglionic fibers travel along the greater petrosal nerve through the pterygoid canal, where they join the postsynaptic fibers of the deep petrosal nerve to become the nerve of the pterygoid canal.

However, the decrease may be significant in conditions of pre-existing decreased renal perfusion, such as renal artery stenosis, heart failure, polycystic kidney disease, or volume depletion. In these patients, the maintenance of GFR depends on angiotensin-II-dependent efferent vasomotor tone. Therefore, renal function should be closely monitored over the first few days after initiation of treatment with ACE inhibitor in patients with decreased renal perfusion. A moderate reduction in renal function, no greater than 30% rise in serum creatinine, that is stabilized after a week of treatment is deemed acceptable as part of the therapeutic effect, providing the residual renal function is sufficient.

The anal wink, anal reflex, perineal reflex, or anocutaneous reflex is the reflexive contraction of the external anal sphincter upon stroking of the skin around the anus. A noxious or tactile stimulus will cause a wink contraction of the anal sphincter muscles and also flexion. The stimulus is detected by the nociceptors in the perineal skin to the pudendal nerve, where a response is integrated by the spinal cord sacral segments S2-S4. The absence of this reflex indicates that there is an interruption of the reflex arc, or damage to the spinal cord, which may be in the sensory afferent limb or the motor efferent limb.

An efferent lymph vessel may directly drain into one of the (right or thoracic) lymph ducts, or may empty into another lymph node as its afferent lymph vessel. Both the lymph ducts return the lymph to the blood stream by emptying into the subclavian veins The functional unit of a lymph vessel is known as a lymphangion, which is the segment between two semilunar valves. Since it is contractile, depending upon the ratio of its length to its radius, it can act either like a contractile chamber propelling the fluid ahead, or as a resistance vessel tending to stop the lymph in its place.

The projection fibers consist of efferent and afferent fibers uniting the cortex with the lower parts of the brain and with the spinal cord. In human neuroanatomy, bundles of axons (nerve fibers) called tracts, within the brain, can be categorized by their function into association fibers, projection fibers, and commissural fibers. In the neocortex, projection neurons are excitatory neurons that send axons to distant brain targets. Considering the six histologically-distinct layers of the neocortex, associative projection neurons extend axons within one cortical hemisphere; commissural projection neurons extend axons across the midline to the contralateral hemisphere; and corticofugal projection neurons extend axons away from cortex.

The axon reflex results in a localized response to only the locally innervated cells of the single neuron where the signal originated. The axon reflex pathway does not include an integration center or synapse that relays communication between neurons in the spinal cord reflex. The stimulus, therefore, is diverted to the effector organ without entering the neuronal cell body and therefore indicates that the axon reflex is not a true reflex where afferent impulses pass through the central nervous system before stimulating efferent neurons. The axon reflex was discovered and was described as "a new type of peripheral reflex" that bypasses the integration center and synapse in the central nervous system.

Unlike the topographic maps of the senses, the neurons of the motor cortex are efferent neurons that exit the brain instead of bringing information to the brain through afferent connections. The motor system is responsible for initiating voluntary or planned movements (reflexes are mediated at the spinal cord level, so movements that associated with a reflex are not initiated by the motor cortex). The activation from the motor cortex travels through Betz cells down the corticospinal tract through upper motor neurons, terminating at the anterior horn of the grey matter where lower motor neurons transmit the signal to peripheral motor neurons and, finally, the voluntary muscles.

Although nausea and vomiting are closely related, some patients experience one symptom without the other and it may be easier to eliminate vomiting than nausea. The vomiting reflex (also called emesis) is thought to have evolved in many animal species as a protective mechanism against ingested toxins. In humans, the vomiting response may be preceded by an unpleasant sensation termed nausea, but nausea may also occur without vomiting. The central nervous system is the primary site where a number of emetic stimuli (input) are received, processed and efferent signals (output) are generated as a response and sent to various effector organs or tissues, leading to processes that eventually end in vomiting.

Increased or decreased blood volume influences blood pressure, which is regulated by baroreceptors, and can in turn affect the strength of ventricular contraction in the heart. Additional research has demonstrated that the subfornical organ may be an important intermediary through which leptin acts to maintain blood pressure within normal physiological limits via descending autonomic pathways associated with cardiovascular control. SFO neurons have also been experimentally shown to send efferent projections to regions involved in cardiovascular regulation including the lateral hypothalamus, with fibers terminating in the supraoptic (SON) and paraventricular (PVN) nuclei, and the anteroventral 3rd ventricle (AV3V) with fibers terminating in the OVLT and the median preoptic area.

Research has implicated the rostral midbrain in the vicinity of the cerebral aqueduct of the third ventricle as the most likely region of damage. A lesion in this area would involve efferent pupillary fibres on the dorsal aspect of the Edinger-Westphal nucleus (associated with the response to light) while sparing the fibres associated with the response to near, which lie slightly more ventrally.Dr Christopher Dente and Dr Andrew Gurwood, The Argyll Robertson Pupil The exact relationship between syphilis and the two types of pupils (AR pupils and tonic pupils) is not known at the present time. The older literature on AR pupils did not report the details of pupillary constriction (brisk vs.

This technique was to prove useful twenty years later, when Chouard showed that children with neonatal deafness need to receive implants as early as possible, before the auditory brain structures begin to atrophy 5. Chouard became familiar with total deafness very early on in his career, since he had direct access to information on the famous electro-therapeutic trials performed by Eyriès in 1957 with André Djourno. Claude-Henri Chouard also identified the functional origins of acoustico-facial anastomoses by following the reconstructed nerve fibres from one end to the other. This helped explain the effectiveness of certain treatments for Menière's disease and revealed the route taken by efferent fibres in the inner ear.

Infiltration from the subarachnoid space into the spinal cord occurs primarily along the perivascular tissues that surround blood vessels at the brain entrance. Infiltration from the anterior median fissure, a 3mm deep furrow on the anterior side of the spinal cord, to the anterior horn of the spinal cord, the ventral grey matter of the spinal cord, is found along the central artery. Direct infiltration of the nerve roots is also observed, mostly from the dorsal roots (the afferent sensory root of the spinal nerve) than the ventral roots (the efferent motor root of a spinal nerve). With mild infiltration, tumor cells are found diffusely in the subarachnoid space from the cervical to sacral levels.

Presynaptic neurons traveling from the spinal cord terminate in the paravertebral ganglia (cervical, thoracic, lumbar, sacral) or the prevertebral ganglia. They synapse with either the postsynaptic neuron of the corresponding level of the spinal cord or ascend and descend to synapse at the lower or upper paravertebral ganglia, respectively. Neurotransmitters are released in the paravertebral ganglia to activate the postganglionic neurons to send efferent sympathetic output to the lower extremities to prepare the body for the “fight or flight” responses. These responses include dilating pupils, constricting blood vessels, and stimulating the secretion of acetylcholine, which causes smooth muscle contraction that leads to an increase in heart rate, blood sugar level, and blood pressure.

Spinal nerve Sympathetic ganglion multilingual Microneurography exploration of sympathetic efferent system is unique from technical point of view as multiunit recordings have been very prosperous whereas single unit recording is essential with most other systems. Soon after microneurography was launched it was demonstrated that sympathetic activity is much different in muscle and skin nerves. Instantaneous sympathetic activity in muscle nerves (MSA / MSNA) is heavily controlled by baroreflex mechanisms, resulting in a characteristic cardiac rhythmicity as well as a close and inverse relation to the small variations of blood pressure that normally occur continuously in phase with respiration. In contrast, the sympathetic activity in skin nerves (SSA/SSNA) lacks a tight relation to cardiac and respiratory events.

In these layers the organization of the two efferent regions of the antennal lobe is represented topographically, establishing a coarse odotopic map of the antennal lobe in the region of the lip of the mushroom bodies. Mushroom bodies are known to be involved in learning and memory, particularly for smell, and thus are the subject of current intense research. In larger insects, studies suggest that mushroom bodies have other learning and memory functions, like associative memory, sensory filtering, motor control, and place memory. Research implies that mushroom bodies generally act as a sort of coincidence detector, integrating multi-modal inputs and creating novel associations, thus suggesting their role in learning and memory.

Release of acetylcholine vesicles from the presynaptic terminal occurs only after adequate depolarization of the efferent nerve. Once a motor nerve action potential reaches the presynaptic nerve terminal it causes an increase in intracellular calcium concentration by causing an increase in ion conductance through voltage gated calcium channels. This increase in calcium concentration allows the acetylcholine vesicles to fuse with the plasma membrane at the presynaptic membrane, in a process called exocytosis, thus releasing acetylcholine into the synapse. Once acetylcholine is present in the synapse it is able to bind to nicotinic acetylcholine receptors increasing conductance of certain cations, sodium and potassium in the postsynaptic membrane and producing an excitatory end т и ироооurrent.

Based on their functional relevance, the SFO neurons can be branded as either GE, featuring nonselective cation channels, or GI, featuring potassium channels. While the afferent projections of the SFO are considered less important than the various efferent connections, it is still notable that the subfornical organ receives synaptic input from the zona incerta and arcuate nucleus. Study of subfornical organ anatomy is still ongoing but evidence has demonstrated slow blood transit time which may facilitate the sensory capability of SFO, enabling increased contact time for blood-borne signals to penetrate its permeable capillaries and influence regulation of blood pressure and body fluids. This observation coincides with the fact that SFO neurons have been shown to be intrinsically osmosensitive.

Lymph capillaries are slightly larger than their counterpart capillaries of the vascular system. Lymph vessels that carry lymph to a lymph node are called afferent lymph vessels, and those that carry it from a lymph node are called efferent lymph vessels, from where the lymph may travel to another lymph node, may be returned to a vein, or may travel to a larger lymph duct. Lymph ducts drain the lymph into one of the subclavian veins and thus return it to general circulation. Generally, lymph flows away from the tissues to lymph nodes and eventually to either the right lymphatic duct or the largest lymph vessel in the body, the thoracic duct.

The RR interval variations present during resting conditions represent beat-by-beat variations in cardiac autonomic inputs. However, efferent vagal (parasympathetic) activity is a major contributor to the HF component, as seen in clinical and experimental observations of autonomic maneuvers such as electrical vagal stimulation, muscarinic receptor blockade, and vagotomy. More problematic is the interpretation of the LF component, which was considered by some as a marker of sympathetic modulation (especially when expressed in normalized units) but is now known to include both sympathetic and vagal influences. For example, during sympathetic activation the resulting tachycardia is usually accompanied by a marked reduction in total power, whereas the reverse occurs during vagal activation.

As a result of such decussations, the efferent connections of the cerebrum to the basal ganglia, the cerebellum and the spine are crossed, and the afferent connections from the spine, the cerebellum and the pons to the thalamus are crossed. As a result, motor, somatosensory, auditory, and visual primary regions in the forebrain represent predominantly the contralateral side of the body. Two of the cranial nerves show chiasmas: the chiasm of the optic tract (cranial nerve II) which originates from the eyes and inserts on the optic tectum of the midbrain, and the trochlear nerve (nerve IV) which originates in the ventral midbrain and innervates one of the six muscles that rotate the eye (superior oblique muscle).

When a muscle is stretched, primary type Ia sensory fibers of the muscle spindle respond to both changes in muscle length and velocity and transmit this activity to the spinal cord in the form of changes in the rate of action potentials. Likewise, secondary type II sensory fibers respond to muscle length changes (but with a smaller velocity-sensitive component) and transmit this signal to the spinal cord. The Ia afferent signals are transmitted monosynaptically to many alpha motor neurons of the receptor-bearing muscle. The reflexly evoked activity in the alpha motoneurons is then transmitted via their efferent axons to the extrafusal fibers of the muscle, which generate force and thereby resist the stretch.

Illustration of Arachnoiditis Arachnoid inflammation can lead to many painful and debilitating symptoms which can vary greatly in each case, and not all people experience all symptoms. Chronic pain is common, including neuralgia, while numbness and tingling of the extremities can occur with spinal cord involvement, and bowel, bladder, and sexual functioning can be affected if the lower part of the spinal cord is involved. While arachnoiditis has no consistent pattern of symptoms, it frequently affects the nerves that supply the legs and lower back. Many patients experience difficulty sitting for long (or even short) periods of time due to discomfort or pain, or because of efferent neurological or other motor symptoms, such as difficulties controlling limbs.

Peripheral nervous system box diagram The classification of peripheral nerves in the peripheral nervous system (PNS) groups the nerves into two main groups, the somatic and the autonomic nervous systems. Together, these two systems provide information regarding the location and status of the limbs, organs, and the remainder of the body to the central nervous system (CNS) via nerves and ganglia present outside of the spinal cord and brain. The somatic nervous system directs all voluntary movements of the skeletal muscles, and can be sub-divided into afferent and efferent neuronal flow. The autonomic nervous system is divided primarily into the sympathetic and parasympathetic nervous systems with a third system, the enteric nervous system, receiving less recognition.

The mammillotegmental fasciculus (or mammillotegmental tract, mammillo- tegmental bundle of Gudden, or Fasciculus mammillotegmentalis) is a small bundle of efferent fibers from the hypothalamus running from the mammillary body to the tegmentum. Its functions are not well defined for humans, but based on animal studies it seems to be related to regulating visceral function and processing spatial information. The mammillotegmental fasciculus was first described by the German neuroanatomist, Bernhard von Gudden, from which it takes its alternate name, mammillo-tegmental bundle of Gudden. The mammillotegmental fasciculus emerges from the principal mammillary fasciculus of the mammillary body and travels dorsally together with the mammillothalamic tract before splitting off and turning caudally to enter the spinal column.

The dorsal nucleus of vagus nerve (or posterior nucleus of vagus nerve or dorsal vagal nucleus or nucleus dorsalis nervi vagi or nucleus posterior nervi vagi) is a cranial nerve nucleus for the vagus nerve in the medulla that lies ventral to the floor of the fourth ventricle. It mostly serves parasympathetic vagal functions in the gastrointestinal tract, lungs, and other thoracic and abdominal vagal innervations. The cell bodies for the preganglionic parasympathetic vagal neurons that innervate the heart reside in the nucleus ambiguus. Additional cell bodies are found in the nucleus ambiguus, which give rise to the branchial efferent motor fibers of the vagus nerve (CN X) terminating in the laryngeal, pharyngeal muscles, and musculus uvulae.

Critics of the polyvagal theory point out that its premises are not supported by empirical, scientific research. Paul Grossman of University Hospital Basel argues that there is no evidence that the dorsal motor nucleus (DMN) is an evolutionarily more primitive center of brainstem parasympathetic system than the nucleus ambiguus (NA), and that no evidence supports the claim that sudden decrease in heartrate elicited by extreme emotional circumstances (like trauma-related dissociation) is due to DMN efferent activity to the heart. In fact, there seems no evidence that such decrease happens in trauma-related dissociation in the first place. Grossman also points out that even the results of Porges' own study on two species of lizard was flawed due to inappropriate measurement of heart rate variability.

The first theory was proposed by William A. Hammond in 1883. This theory posits that achiria (the term was not officially coined at the time) is caused by an obstruction in the efferent path, which results in impulses being passed to the contralateral side of the body, hence reaching the cerebral hemisphere opposite to where the impulses originated from. In 1891, Albert Paul Weiss tried to validate this theory by blocking the posterior columns of the spinal cord. Bosc also did a similar demonstration in 1892, but he blocked one side of the cerebral hemisphere instead of the spinal cord, such that the signals trying to get to that hemisphere have to pass through the corpus callosum to the opposite hemisphere instead of other pathways.

While conducting research into the (afferent) sensory nervous system with evoked potentials, Sgro also began to investigate devices and techniques to determine the state of the (efferent) motor nervous system using TMS with the goal of more effective detection of sub-clinical diseases and increased sensitivity of the motor system during intra-operative patient monitoring. Sgro and his associates studied the theoretical and practical issues involved in the design of a high magnetic field strength and rapid transcranial magnetic stimulator which could exceed the historical safety limit of electrical brain stimulation (40 uC/cm2/phase at a stimulation rate of 20 to 50 Hertz over several hours). These studies resulted in the construction of a rapid high magnetic field strength device which was suitable for safety studies.

Vocal cord paresis, also known as recurrent laryngeal nerve paralysis or vocal fold paralysis, is an injury to one or both recurrent laryngeal nerves (RLNs), which control all muscles of the larynx except for the cricothyroid muscle. The RLN is important for speaking, breathing and swallowing. The primary larynx-related functions of the mainly efferent nerve fiber RLN, include the transmission of nerve signals to the muscles responsible for regulation of the vocal folds' position and tension to enable vocalization, as well as the transmission of sensory nerve signals from the mucous membrane of the larynx to the brain. A unilateral injury of the nerve typically results in hoarseness caused by a reduced mobility of one of the vocal folds.

Motor nerve of Ox A motor nerve is a nerve located in the central nervous system (CNS), usually the spinal cord, that sends motor signals from the CNS to the muscles of the body. This is different from the motor neuron, which includes a cell body and branching of dendrites, while the nerve is made up of a bundle of axons. Motor nerves act as efferent nerves which carry information out from the CNS, as opposed to afferent nerves (also called sensory nerves), which send signals from sensory receptors in the periphery to the CNS. There are also nerves that serve as both sensory and motor nerves called mixed nerveMotor nerve fibers transduce signals from the CNS to peripheral neurons of proximal muscle tissue.

Ghrelin is a participant in regulating the complex process of energy homeostasis which adjusts both energy input – by adjusting hunger signals – and energy output – by adjusting the proportion of energy going to ATP production, fat storage, glycogen storage, and short-term heat loss. The net result of these processes is reflected in body weight, and is under continuous monitoring and adjustment based on metabolic signals and needs. At any given moment in time, it may be in equilibrium or disequilibrium. Gastric-brain communication is an essential part of energy homeostasis, and several communication pathways are probable, including the gastric intracellular mTOR/S6K1 pathway mediating the interaction among ghrelin, nesfatin and endocannabinoid gastric systems, and both afferent and efferent vagal signals.

The pallial portions build the analytic or perceptual end of this complex, whereas the subpallial portions represent the corresponding output or efferent functional pole. The olfactory bulb is a peculiar pallial outgrowth (maybe induced by the primary olfactory fibers afferent to it, coming from the sensory neurons developed in the olfactory placode) whose projection neurons (the mitral and tufted neurons) are pallial in origin and accordingly excitatory. In contrast, the superfial periglomerulary neurons, various intermediate interneurons and the deep granule cells are all of subpallial origin and migrate tangentially out of the striatal part of the subpallium (apparently from a dorsal subsector of this domain) through the so-called rostral migratory stream into the olfactory bulb. These extremely numerous subpallial cells are all inhibitory.

The cerebral cortex is connected to various subcortical structures such as the thalamus and the basal ganglia, sending information to them along efferent connections and receiving information from them via afferent connections. Most sensory information is routed to the cerebral cortex via the thalamus. Olfactory information, however, passes through the olfactory bulb to the olfactory cortex (piriform cortex). The majority of connections are from one area of the cortex to another, rather than from subcortical areas; Braitenberg and Schüz (1998) claim that in primary sensory areas, at the cortical level where the input fibres terminate, up to 20% of the synapses are supplied by extracortical afferents but that in other areas and other layers the percentage is likely to be much lower.

The somatic nervous system controls all voluntary muscular systems within the body, and the process of voluntary reflex arcs. The basic route of nerve signals within the efferent somatic nervous system involves a sequence that begins in the upper cell bodies of motor neurons (upper motor neurons) within the precentral gyrus (which approximates the primary motor cortex). Stimuli from the precentral gyrus are transmitted from upper motor neurons and down the corticospinal tract, via axons to control skeletal (voluntary) muscles. These stimuli are conveyed from upper motor neurons through the ventral horn of the spinal cord, and across synapses to be received by the sensory receptors of alpha motor neurons (large lower motor neurons) of the brainstem and spinal cord.

There is much debate about the true cause and mechanism of the sneezing fits brought about by the photic sneeze reflex. Sneezing occurs in response to irritation in the nasal cavity, which results in an afferent nerve fiber signal propagating through the ophthalmic and maxillary branches of the trigeminal nerve to the trigeminal nerve nuclei in the brainstem. The signal is interpreted in the trigeminal nerve nuclei, and an efferent nerve fiber signal goes to different parts of the body, such as mucous glands and the thoracic diaphragm, thus producing a sneeze. The most obvious difference between a normal sneeze and a photic sneeze is the stimulus: normal sneezes occur due to irritation in the nasal cavity, while the photic sneeze can result from a wide variety of stimuli.

Following these findings with funding from the Whitaker Foundation,The Development of Methods for the Analysis of Non-Time-Stable Brain Responses. Whitaker Foundation grant, 1985-1989 Sgro developed technology and techniques to analyze evoked potentials based on stimulation run by an ultra fast (i.e. hundreds of hertz) pseudorandom m-sequences.Marmarmelis, P. and Marmarmelis, V.Z., Analysis of PhysiologicalSystem, Plenum Press, New York, NY, 1978. This work was demonstrated to be a more effective method of identification and predictor of sub-clinical diseases or damage such as mortality from status epilepticus"Assessment of Afferent and Efferent Neuropathways in Severe Head Injury," NIH Program Project Grant #2P01NS012587, 1989-1992.. (diseases that otherwise went undetected until they become severe enough to qualify as clinically apparent when compared to conventional evoked potentials).

Bogorad's syndrome, also known as "Crocodile Tears Syndrome", is an uncommon consequence of nerve regeneration subsequent to Bell's palsy or other damage to the facial nerve. Efferent fibers from the superior salivary nucleus become improperly connected to nerve axons projecting to the lacrimal glands, causing one to shed tears (lacrimate) on the side of the palsy during salivation while smelling foods or eating. It is presumed that this would cause salivation while crying due to the inverse improper connection of the lacrimal nucleus to the salivary glands, but this would be less noticeable. The condition was first described in 1926 by its namesake, Russian neuropathologist F. A. Bogorad, in an article titled "Syndrome of the Crocodile Tears" (alternatively, "The Symptom of the Crocodile Tears") that argued the tears were caused by the act of salivation.

There are CD4+ Th lymphocytes in germinal centres and interfollicular area and CD8+ T cells mainly in interfollicular area. High endothelial venules (HEVs) are also present in BALT in T/B-cell interface, allowing for the recruitment of naive T cells. These HEV are the only entry site for lymphocytes to migrate into the BALT and leave by efferent lymphatic vessels. In some species, M cells have been described in epithelium above BALT similar to M cells in the dome epithelium of Peyer’s patches, although the dome epithelium is not typical for BALT. For formation of BALT in mice is necessary inteleukin-17 and VCAM-1, PNAd and LFA-1 and it is lymphotoxin-α independent whereas the development of secondary lymphoid organs (such as lymph nodes and Peyer’s patches) is typically dependent on LTα.

Severe hypotonia in infancy commonly known as floppy baby syndrome. Recognizing hypotonia, even in early infancy, is usually relatively straightforward, but diagnosing the underlying cause can be difficult and often unsuccessful. The long-term effects of hypotonia on a child's development and later life depend primarily on the severity of the muscle weakness and the nature of the cause. Some disorders have a specific treatment but the principal treatment for most hypotonia of idiopathic or neurologic cause is physical therapy, occupational therapy for remediation, and/or music therapy. Hypotonia is thought to be associated with the disruption of afferent input from stretch receptors and/or lack of the cerebellum’s facilitatory efferent influence on the fusimotor system, the system that innervates intrafusal muscle fibers thereby controlling muscle spindle sensitivity.

The submandibular lymph nodes (submaxillary glands in older texts), three to six in number, are placed beneath the body of the mandible in the submandibular triangle, and rest on the superficial surface of the submandibular gland. One gland, the middle gland of Stahr, which lies on the facial artery as it turns over the mandible, is the most constant of the series; small lymph glands are sometimes found on the deep surface of the submandibular gland. The afferents of the submandibular glands drain the medial canthus, the cheek, the side of the nose, the upper lip, the lateral part of the lower lip, the gums, and the anterior part of the margin of the tongue. Efferent lymph vessels from the facial and submental lymph nodes also enter the submandibular glands.

There are three major types of bladder dysfunction due to neural lesions: (1) the type due to interruption of the afferent nerves from the bladder; (2) the type due to interruption of both afferent and efferent nerves; and (3) the type due to interruption of facilitatory and inhibitory pathways descending from the brain. In all three types the bladder contracts, but the contractions are generally not sufficient to empty the viscus completely, and residual urine is left in the bladder. Paruresis, also known as shy bladder syndrome, is an example of a bladder interruption from the brain that often causes total interruption until the person has left a public area. As these people may have difficulty urinating in the presence of others and will consequently avoid using urinals directly adjacent to another person.

She is known for her elucidation of function along the hypothalamic, pituitary, adrenal axis, and the discovery that comfort foods dampen the stress response. Her lab explored the role of glucocorticoid feedback on the HPA axis, showing that there is a very fast (seconds-minutes) inhibitory effect, and that sufficiently intense stimuli to the stress-response system use central networks that appear to bypass central glucocorticoid inhibition of subsequent system activity. The lab also provided evidence that efferent adrenal nerves regulate both compensatory adrenal growth after unilateral adrenalectomy, and the diurnal rhythm in adrenocortical sensitivity to ACTH secretion. The finding that body weight, fat content, and activity in the HPA axis are tightly correlated, initiated subsequent studies that ultimately showed that only voluntary intake of lard inhibits adrenocortical responses to subsequent stressors.

For instance, the arterial blood pressure in mammals is homeostatically controlled, and measured by stretch receptors in the walls of the aortic arch and carotid sinuses at beginnings of the internal carotid arteries. The sensors send messages via sensory nerves to the medulla oblongata of the brain indicating whether the blood pressure has fallen or risen, and by how much. The medulla oblongata then distributes messages along motor or efferent nerves belonging to the autonomic nervous system to a wide variety of effector organs, whose activity is consequently changed to reverse the error in the blood pressure. One of the effector organs is the heart whose rate is stimulated to rise (tachycardia) when the arterial blood pressure falls, or to slow down (bradycardia) when the pressure rises above set point.

In neuroscience, an F wave is one of several motor responses which may follow the direct motor response (M) evoked by electrical stimulation of peripheral motor or mixed (sensory and motor) nerves. F-waves are the second of two late voltage changes observed after stimulation is applied to the skin surface above the distal region of a nerve, in addition to the H-reflex (Hoffman's Reflex) which is a muscle reaction in response to electrical stimulation of innervating sensory fibers. Traversal of F-waves along the entire length of peripheral nerves between the spinal cord and muscle, allows for assessment of motor nerve conduction between distal stimulation sites in the arm and leg, and related motoneurons (MN's) in the cervical and lumbosacral cord. F-waves are able to assess both afferent and efferent loops of the alpha motor neuron in its entirety.

In the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the distal tubule, at the point where the thick ascending limb of the Loop of Henle meets the distal convoluted tubule. The macula densa is the thickening where the distal tubule touches the glomerulus. The cells of the macula densa are sensitive to the concentration of sodium chloride in the distal convoluted tubule. A decrease in sodium chloride concentration initiates a signal from the macula densa that has two effects: (1) it decreases resistance to blood flow in the afferent arterioles, which raises glomerular hydrostatic pressure and helps return the glomerular filtration rate (GFR) toward normal, and (2) it increases renin release from the juxtaglomerular cells of the afferent and efferent arterioles, which are the major storage sites for renin.

People treated with ARBs including valsartan or diuretics and are susceptible to conditions of developing low renal blood flow such as abnormal narrowing of blood vessel in kidney, hypertension, renal artery stenosis, heart failure, chronic kidney disease, severe congestive heart failure, or volume depletion whose renal function is in part dependent on the activity of the renin-angiotensin system like efferent arteriolar vasoconstriction done by angiotensin II are at high risk of deterioration of renal function comprising acute kidney failure, oliguria, worsening azotemia or heightened serum creatinine. When blood flow to the kidneys is reduced, the kidney activates a series of response that triggers angiotensin release to constrict blood vessels and facilitate blood flow in the kidney. So long as the nephron function degradation is being progressive or reaches clinically significant level, withhold or discontinue valsartan is warranted.

The internal globus pallidus (GPi or medial globus pallidus; in rodents its homologue is known as the entopeduncular nucleus) and the external globus pallidus (GPe) make up the globus pallidus. The GPi is one of the output nuclei of the basal ganglia (the other being the substantia nigra pars reticulata). The GABAergic neurons send their axons to the ventral anterior nucleus (VA) and the ventral lateral nucleus (VL) in the dorsal thalamus, to the centromedian complex, and to the pedunculopontine complex. The efferent bundle is constituted first of the ansa and lenticular fasciculus, then crosses the internal capsule as the Edinger's comb system then arrives at the laterosuperior corner of the subthalamic nucleus and constitutes the field H2 of Forel, then H, and suddenly changes its direction to form field H1 that goes to the inferior part of the thalamus.

The name is derived from the surgeon who first described it (César Roux) and the stick-figure representation. Diagrammatically, the Roux-en-Y anastomosis looks a little like the letter Y. Typically, the two upper limbs of the Y represent (1) the proximal segment of stomach and the distal small bowel it joins with and (2) the blind end that is surgically divided off, and the lower part of the Y is formed by the distal small bowel beyond the anastomosis. Roux-en-Ys are used in several operations and collectively called Roux operations. When describing the surgery, the Roux limb is the efferent or antegrade limb that serves as the primary recipient of food after the surgery, while the hepatobiliary or afferent limb that anastomoses with the biliary system serves as the recipient for biliary secretions, which then travel through the excluded small bowel to the distal anastomosis at the mid jejunum to aid digestion.

First, the belief that mental illness was organic in nature, and reflected an underlying brain pathology; next, that the nervous system was organized according to an associationist model comprising an input or afferent system (a sensory center), a connecting system where information processing took place (an association center), and an output or efferent system (a motor center); and, finally, a modular conception of the brain whereby discrete mental faculties were connected to specific regions of the brain. Burckhardt's hypothesis was that by deliberately creating lesions in regions of the brain identified as association centers a transformation in behavior might ensue. According to his model, those mentally ill might experience "excitations abnormal in quality, quantity and intensity" in the sensory regions of the brain and this abnormal stimulation would then be transmitted to the motor regions giving rise to mental pathology. He reasoned, however, that removing material from either of the sensory or motor zones could give rise to "grave functional disturbance".

Autogenic inhibition refers to a reduction in excitability of a contracting or stretched muscle, that in the past has been solely attributed to the increased inhibitory input arising from Golgi tendon organs (GTOs) within the same muscle. It was first thought GTOs only had protective function which was to prevent muscles from damages because of the assumptions that they always inhibited motoneurons and that they fired only under high tension. But it is now known that GTOs signal muscle tension continuously providing precise information about muscle force, that the reflex pathway has multisensory inputs that may allow precise control of muscle forces for fine activities, and that Ib fibers connect widely with motoneurons innervating muscles acting on different joints, which when complemented with their reflex pathways, are part of reflex networks that control movements of the whole limbs. The reduced efferent (motor) drive to the muscle by way of autogenic inhibition is a factor historically believed to assist target muscle elongation, although current literature casts doubt on this hypothesis.