156 Sentences With "nerve fibres" | Random Sentence Generator

The nerve fibres that connect the brain's right and left hemispheres were barely recognizable.

Jaynes believed that the development of nerve fibres connecting the two hemispheres gradually integrated brain function.

Though outside the body, these stem cells, shown in magenta, were able to generate nerve fibres, shown in green.

The condition is almost always caused by neuropathy, an interruption in the transmission of painful sensation along nerve fibres.

"What we discovered is that it's actually the connections between the sensory cells and the nerve fibres that go first," Liberman told me.

Multiple sclerosis (MS) happens when the body's immune system learns to attack its own nerve fibres in the same way that it learns to attack invading pathogens.

Later, in New York, by means of another, more complex implant in his arm, Warwick connected the nerve fibres in his wrist and hand to a computer.

Connecting Broca's area with Wernicke's is a neural network: a thick, curving bundle of billions of nerve fibres, the arcuate fasciculus, which integrates the production and the comprehension of language.

Neurofilament light chain is a protein found in blood that provides structural support to nerve fibres in the brain, and increases may be associated with nerve cell damage, Roche said in a statement on Tuesday.

Many involve lengthy operations, implanting electrodes in the subject's brain or harvesting tissue from nerve-dense parts of the body so there are sufficient nerve fibres in the region where the bionic device is being attached.

When she was twenty, she received a cochlear implant—a surgically placed electronic device that transmits sound impulses from a microphone near the ear to electrodes in the cochlea, bypassing the eardrum and directly stimulating the hair cells and the auditory nerve fibres.

Scientists had known for a long time that most hearing impairment involves damage to the synapses and nerve fibres to which hair cells are attached, but they had assumed that the nerve damage followed hair-cell loss, and was a consequence of it.

"From what I do know about certain forms of energy that are medically used to remove nerve fibres, such as to reduce pain, I can't understand how any source would be so selective to only injure the brain and not peripheral nerves and the spinal cord," he said.

By 2009 Dr Burt, now at Northwestern University, in Chicago, had proved that his treatment worked in patients with the most common form of the disease, relapsing remitting MS. The treatment involves using lower-dose chemotherapy to kill the white blood cells that are responsible for attacking nerve fibres, and then rebooting the immune system using stem cells collected from the patient before treatment began.

Subjects are all called in, given screening tests (to exclude those with abnormal drug regimens or excessive suicidality) then subjected to several quantitative sensory tests: Participants are asked to immerse one naked foot in a bucket of iced water until they feel pain; then one arm is subjected to a contact heat evoked potential simulator, which gradually heats up small-diameter nerve fibres until the patient feels pain; then they have pressure needles poked onto their skin without breaking it until they report discomfort.

It sends nerve fibres to the subthalamic nucleus and putamen. It receives nerve fibres from the cerebral cortex, vestibular nuclei, globus pallidus, superior colliculus, reticular formation, and spinothalamic tract.

Together with the Swiss physiologist Robert Stämpfli, he evidenced the existence of saltatory conduction in myelinated nerve fibres.

The degenerating axons formed droplets that could be stained, thus allowing for studies of the course of individual nerve fibres.

These act on receptors on the afferent nerve fibres which lie in apposition to the glomus cell to cause an action potential.

The following year she moved to Freiburg for a semester, where she attended the lectures of Paul Trendelenburg. She then returned to Bonn for her final year. In Bonn she was supervised by Professor Ceelen, a pathological anatomist. For her dissertation, she applied a technique she had learned from Boeke on how to stain nerve fibres to the cells of phaeochromocytoma, showing they also pushed out nerve fibres.

There are two types of nerve fibre relevant to pain in fish. Group C nerve fibres are a type of sensory nerve fibre which lack a myelin sheath and have a small diameter, meaning they have a low nerve conduction velocity. The suffering that humans associate with burns, toothaches, or crushing injury are caused by C fibre activity. A typical human cutaneous nerve contains 83% Group C nerve fibres.

The auditory nerve fibres, known as the afferent nerve fibres, carry information from the organ of Corti to the brainstem and brain. Auditory afferent fibres consist of two types of fibres called type I and type II fibres. Type I fibres innervate the base of one or two inner hair cells and Type II fibres innervate the outer hair cells. Both leave the organ of Corti through an opening called the habenula perforata.

Angélique Arvanitaki (11 July 1901 – 6 October 1983) was a French neurophysiologist who did research on the electrical activity of neurons using the large nerve fibres of several different molluscs.

The crossing of nerve fibres, and the impact on vision that this had, was probably first identified by Persian physician "Esmail Jorjani", who appears to be Zayn al-Din Gorgani (1042–1137).

In the spine, similar fibres join the intervertebral disc to the adjacent vertebrae. Each fibre is accompanied by an arteriole and one or more nerve fibres. Scottish anatomist William Sharpey described them in 1846.

In Search of Memory: The Emergence of a New Science of Mind - Eric R. Kandel Google Books These nerve fibres are part of the autonomic nervous system, part of the 'fight or flight' system.

Närhi M, Jyväsjärvi E, Virtanen A, Huopaniemi T, Ngassapa D, Hirvonen T. Role of intradental A- and C-type nerve fibres in dental pain mechanisms. Proc Finn Dent Soc. 1992;88 Suppl 1:507-16. Review.

The organ consists of a minute skin papilla with 0.1–0.2 mm diameter. At the papilla's core, a geometric constellation of nerve fibres with free endings is embedded symmetrically in a column of epithelial cells. Eimer saw two to three single nerve fibres, rising straight in the middle of the column and ending in the fifth layer under the stratum corneum that forms the hard top of the epidermis. The fibres extend short protrusions perpendicularly into each epithelial layer they traverse, where the protrusions end in 'buttons'.

Most corneal nerve fibres are sensory in origin and are derived from the ophthalmic branch of the trigeminal nerve.L. J. Muller et al., Corneal nerves: structure, contents and function. Experimental Eye Research, 76 (2003) 521-542.

Arvanitaki contributed to the field of neurophysiology with research that explored the giant nerve fibres in genera of gastropods, the sea hare Aplysia and the land snail Helix. She developed the concept of ganglion preparation of large identifiable nerves. Arvanitaki also discovered that regular electrical oscillations could periodically grow in size until a series of action potentials were fired along isolated nerve fibres of the cuttlefish, genus Sepia. A further contribution of Arvanitaki was the demonstration that a neuronal circuit was not required for a single nerve to produce rhythmic and spontaneous activity.

The long digital extensor muscle (usually in the hind limb) is the muscle that appears to be the most affected by this condition. The most severe muscle lesions have been found within the long and lateral digital extensors and lateral deep digital flexor. The location of neuromuscular lesions in Australian stringhalt may be explained by the susceptibility of longer, larger myelinated nerve fibres to injury. Regenerating nerve fibres with disproportionately thin myelin sheaths are more common in the proximal parts of affected nerves in horses with Australian stringhalt.

The muscle is innervated by the posterior branch of axillary nerve where it forms a pseudoganglion. A pseudoganglion has no nerve cells but nerve fibres are present. Damage to the fibers innervating the teres minor is clinically significant.

When rods and cones are stimulated by light, they connect through adjoining cells within the retina to send an electrical signal to the optic nerve fibres. The optic nerves send off impulses through these fibres to the brain.

The minimal effective (i.e., threshold) stimulus is adequate only for fibres of high excitability, but a stronger stimulus excites all the nerve fibres. Increasing the stimulus further does increase the response of whole nerve. Heart muscle is excitable, i.e.

Because each nerve may have several functions, the nerve fibres that make up the nerve may collect in more than one nucleus. For example, the trigeminal nerve (V), which has a sensory and a motor role, has at least four nuclei.

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.

Commisure of Gudden. e. Fibres that continue in a different depth. (from: Cajal, Fig. 6) In mammals and birds and other vertebrates with frontal eyes, the optic nerves do blend in the optic chiasm, and only part of the nerve fibres cross the midline.

While the risks of blood loss and infection are low, anesthesia is, however necessary, as the burdizzo causes blunt force trauma to the spermatic cords, which are thickly wrapped in nerve fibres. So therefore, human use is disadvantageous as it may involve testicular infections.

Injury to both the right and left nerve may result in more serious damage, such as the inability to speak. Additional problems may emerge during healing, as nerve fibres that re-anastamose may result in vocal cord motion impairment, uncoordinated movements of the vocal cord.

They are ringed by a circle of roughly 19 evenly spaced nerve fibres, known as satellite fibres, whose protrusions point inwards. In addition, Eimer distinguished a separate set of nerve fibres with free nerve endings. By contrast to the fibres in the papilla's core, these travel obliquely toward the surface at the papilla's perimeter. With improved histological techniques, a second touch receptor type, Merkel cell-neurite complexes, was found in the stratum germinativum at the bottom of the epidermis, and a third, lamellated corpuscles of Vater and Pacini, was discovered in the stratum papillare of the dermis underneath the Merkel cells as published by Halata in 1975.

It has been argued that fish can not feel pain because they do not have a sufficient density of appropriate nerve fibres. A typical human cutaneous nerve contains 83% GroupC nerve fibres, however, the same nerves in humans with congenital insensitivity to pain have only 24–28% C-type fibres. Based on this, James Rose, from the University of Wyoming, has argued that the absence of C-type fibres in cartilagenous sharks and rays indicates that signalling leading to pain perception is likely to be impossible, and the low numbers for bony fish (e.g. 5% for carp and trout) indicate this is also highly unlikely for these fish.

From 1896 to 1910 Tuckett was an active researcher and published many papers in the Journal of Physiology. He wrote an important paper on the structure of non-meduallated nerve fibres. He was elected a member of The Physiological Society in 1896.Anonymous. (1943). Ivor Lloyd Tuckett.

For example, the fruit fly's compound eye is made of hundreds of small lensed structures (ommatidia); the human eye has a blind spot where the optic nerve enters the eye, and the nerve fibres run over the surface of the retina, so light has to pass through a layer of nerve fibres before reaching the detector cells in the retina, so the structure is effectively "upside-down"; in contrast, the cephalopod eye has the retina, then a layer of nerve fibres, then the wall of the eye "the right way around". The evidence of pax-6, however, was that the same genes controlled the development of the eyes of all these animals, suggesting that they all evolved from a common ancestor. Ancient genes had been conserved through millions of years of evolution to create dissimilar structures for similar functions, demonstrating deep homology between structures once thought to be purely analogous. This notion was later extended to the evolution of embryogenesis and has caused a radical revision of the meaning of homology in evolutionary biology.

Transactions of the American Philosophical Society. 44, Issue 2, 139–317. He is best known for reducing Karl Ernst von Baer's four germ layers to three: the ectoderm, mesoderm, and endoderm. He also discovered unmyelinated nerve fibres and the nerve cells in the heart sometimes called Remak's ganglia.

Esophageal and anal rings of A. caninum are the source of nerve fibres that extend throughout the body to innervate sensory organs, including amphids and phasmids. Eggs are laid by the females, typically when at the eight-cell stage. Eggs are 38–43 μm in width, with thin walls.

Auditory-nerve fibres are able to represent low-frequency sounds via their phase-locked discharges (i.e., TFSn information). The upper frequency limit for phase locking is species dependent. It is about 5 kHz in the cat, 9 kHz in the barn owl and just 4 kHz in the guinea pig.

Destruction of the nerve fibres causes neuropeptides to be released into pulp. The neuropeptides can cause an increase vascular permeability and vasodilation. The filtration of serum proteins and fluid from the vessel causes the tissue to become oedematous. The tissue pressure increases as the blood volume and interstitial fluid volume rises.

The pedal ganglia, which control the foot, are at its base, and the visceral ganglia, which can be quite large in swimming bivalves, are under the posterior adductor muscle. These ganglia are both connected to the cerebropleural ganglia by nerve fibres. Bivalves with long siphons may also have siphonal ganglia to control them.

These receptors are abundant and distributed all over the epidermis. Each receptor shows a slightly elevated cuticle which covers a group of tall, slender and columnar receptor cells. These cells bear small hairlike processes at their outer ends and their inner ends are connected with nerve fibres. The epidermal receptors are tactile in function.

These electrical impulses coordinate contraction throughout the remaining heart muscle via the electrical conduction system of the heart. Sinoatrial node activity is modulated, in turn, by nerve fibres of both the sympathetic and parasympathetic nervous systems. These systems act to increase and decrease, respectively, the rate of production of electrical impulses by the sinoatrial node.

The olivocochlear system is a component of the auditory system involved with the descending control of the cochlea. Its nerve fibres, the olivocochlear bundle (OCB), form part of the vestibulocochlear nerve (VIIIth cranial nerve, also known as the auditory-vestibular nerve), and project from the superior olivary complex in the brainstem (pons) to the cochlea.

Non-invasive, simple treatments which can be carried out at home should be attempted before in-office procedures are carried out. The purported mechanism of action of these treatments is either occlusion of dentin tubules (e.g. resins, varnishes, toothpastes) or desensitization of nerve fibres/blocking the neural transmission (e.g. potassium chloride, potassium citrate, potassium nitrate).

A gamma motor neuron (γ motor neuron), also called gamma motoneuron, is a type of lower motor neuron that takes part in the process of muscle contraction, and represents about 30% of ( Aγ ) fibers going to the muscle.Hunt, C. (1951) "The reflex activity of mammalian small-nerve fibres." Journal of Physiology. 115(4): 456–469.

The sympathetic trunk is a fundamental part of the sympathetic nervous system, and part of the autonomic nervous system. It allows nerve fibres to travel to spinal nerves that are superior and inferior to the one in which they originated. Also, a number of nerves, such as most of the splanchnic nerves, arise directly from the trunks.

Schwann cells are a variety of glial cells that keep peripheral nerve fibres (both myelinated and unmyelinated) alive. In myelinated axons, Schwann cells form the myelin sheath. The sheath is not continuous. Individual myelinating Schwann cells cover about 100 μm of an axon—equating to about 10,000 Schwann cells along a 1-m length of the axon.

Synucleinopathies (also called α-Synucleinopathies) are neurodegenerative diseases characterised by the abnormal accumulation of aggregates of alpha- synuclein protein in neurons, nerve fibres or glial cells. There are three main types of synucleinopathy: Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Other rare disorders, such as various neuroaxonal dystrophies, also have α-synuclein pathologies.

The hypoglossal nerve may be connected (anastamosed) to the facial nerve to attempt to restore function when the facial nerve is damaged. Attempts at repair by either wholly or partially connecting nerve fibres from the hypoglossal nerve to the facial nerve may be used when there is focal facial nerve damage (for example, from trauma or cancer).

Neuroprotection is also a concept used in ophthalmology regarding glaucoma. The only neuroprotection currently proven in glaucoma is intraocular pressure reduction. However, there are theories that there are other possible areas of neuroprotection, such as protecting from the toxicity induced by degenerating nerve fibres from glaucoma. Cell culture models show that retinal ganglion cells can be prevented from dying by certain pharmacological treatments.

Crayfish have peripheral nerve fibres which are responsive to noxious stimuli. Neurons functionally specialized for nociception have been documented in other invertebrates including the leech Hirudo medicinalis, the nematode Caenorhabditis elegans and the molluscs Aplysia californica and Cepaea nemoralis. Changes in neuronal activity induced by noxious stimuli have been recorded in the nervous centres of Caenorhabditis elegans, Drosophila melanogaster and larval Manduca sexta.

Cones are mostly concentrated in and near the fovea. Only a few are present at the sides of the retina. Objects are seen most sharply in focus when their images fall on the fovea, as when one looks at an object directly. Cone cells and rods are connected through intermediate cells in the retina to nerve fibres of the optic nerve.

EC cells typically extend down to the basal lamina with cytoplasmic extensions known to pass through the connective tissue and neighbouring glands. Tissue beneath EC cells typically contains abundant fenestrated capillaries, lymph vessels and small unmyelinated nerve fibres. Secreted serotonin can either be taken up into residing vessels (transported in the blood by platelets) or act on nerve synaptic terminals.

The gate control theory explains that pain can be reduced if the touch nerve fibres are stimulated due to non-harmful stimuli. Advancement in techniques used to deliver local anaesthesia are very important. There are types of local anaesthesia that apply vibrations to the skin while the injection is being placed into the skin. This uses the gate control theory to minimise pain to the patient.

Merciful anosmia is a condition in which the person is unaware of a foul smell emanating from his own nose. This condition is seen in atrophic rhinitis. In atrophic rhinitis, the turbinates, venous sinusoids, seromucinous glands and nerves undergo atrophy, resulting in a foul smelling discharge. As the nerve fibres sensing smell are also atrophied, the patient is unable to appreciate the foul smell.

The dorsal root of spinal nerve (or posterior root of spinal nerve) is one of two "roots" which emerge from the spinal cord. It emerges directly from the spinal cord, and travels to the dorsal root ganglion. Nerve fibres with the ventral root then combine to form a spinal nerve. The dorsal root transmits sensory information, forming the afferent sensory root of a spinal nerve.

The root emerges from the posterior part of the spinal cord and travels to the dorsal root ganglion. The dorsal root ganglia contain the pseudo-unipolar cell bodies of the nerve fibres which travel from the ganglia through the root into the spinal cord. The lateral division of the dorsal root contains lightly myelinated and unmyelinated fibres of small diameter. These carry pain and temperature sensation.

Section of retina bipolar and horizontal cells (yellow layer), then to the amacrine cells and ganglion cells (purple layer), then to the optic nerve fibres. The signals are processed in these layers. First, the signals start as raw outputs of points in the rod and cone cells. Then the nerve layers identify simple shapes, such as bright points surrounded by dark points, edges, and movement.

Mucoperiosteum is a compound structure consisting of mucous membrane and underlying periosteum. It includes epithelium and lamina propria, but attaches directly to the periosteum of underlying bone without the usual submucosa. It consists of loose fatty or glandular tissues; with blood vessels & nerve fibres that supply the mucosa. It can be found in the midline of the hard palate, the palatine raphe, among other places.

Diabetic neuropathy of the oculomotor nerve in a majority of cases does not affect the pupil. The sparing of the pupil is thought to be associated with the microfasciculation of the fibers which control the pupillomotor function located on the outmost aspect of the occulomotor nerve fibres; these fibres are spared because they are outermost and so less prone to ischaemic damage than the innermost fibres.

These structures work harmoniously to produce different cognitions within the brain. One of the largest proposals for this ideology is that of Diffusion Tensor Imaging. This technique traces the differing pathways of nerve fibres that further create communication throughout differing structures. These networks can be thought of as neural maps that can expand or contract according to the information being processed at that time.

Epidural analgesia causes a loss of sensation, including pain, by blocking the transmission of signals through nerve fibres in or near the spinal cord. For this reason, epidurals are commonly used for pain control during childbirth and surgery. The technique is considered safe and effective for these purposes. When used during childbirth, there is no difference in adverse effects between earlier or later administration.

English anatomist Thomas Willis in 1664 first described the accessory nerve, choosing to use "accessory" (described in Latin as nervus accessorius) meaning in association with the vagus nerve. In 1848, Jones Quain described the nerve as the "spinal nerve accessory to the vagus", recognizing that while a minor component of the nerve joins with the larger vagus nerve, the majority of accessory nerve fibres originate in the spinal cord. In 1893 it was recognised that the heretofore named nerve fibres "accessory" to the vagus originated from the same nucleus in the medulla oblongata, and it came to pass that these fibres were increasingly viewed as part of the vagus nerve itself. Consequently, the term "accessory nerve" was and is increasingly used to denote only fibres from the spinal cord; the fact that only the spinal portion could be tested clinically lent weight to this opinion.

In the gastrointestinal tract, mucosal mast cells are located in close proximity to sensory nerve fibres, which communicate bidirectionally. When these mast cells initially degranulate, they release mediators (e.g., histamine, tryptase, and serotonin) which activate, sensitize, and upregulate membrane expression of nociceptors (i.e., TRPV1) on visceral afferent neurons via their receptors (respectively, HRH1, HRH2, HRH3, PAR2, 5-HT3); in turn, neurogenic inflammation, visceral hypersensitivity, and intestinal dysmotility (i.e.

Carl Freiesleben quoted in . After severing his official connections, he awaited an opportunity to fulfill his long-cherished dream of travel. Humboldt was able to spend more time on writing up his research. He had used his own body for experimentation on muscular irritability, recently discovered by Luigi Galvani and published his results, (Berlin, 1797) (Experiments on Stimulated Muscle and Nerve Fibres), enriched in the French translation with notes by Blumenbach.

Spontaneous venous pulsations are present in about 80 percent of patients with ODD, but absent in cases of true disc edema. Other causes of disc elevation clinicians must exclude may be: hyaloid traction, epipapillary glial tissue, myelinated nerve fibres, scleral infiltration, vitreopapillary traction and high hyperopia. Disorders associated with disc elevation include: Alagille syndrome, Down syndrome, Kenny-Caffey syndrome, Leber Hereditary Optic Neuropathy and linear nevus sebaceous syndrome.

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.

Early in the 20th century, the function of the ampullae was not clearly understood, and electrophysiological experiments suggested a sensibility to temperature, mechanical pressure and possibly salinity. It was not until 1960 that the ampullae were clearly identified as specialized receptor organs for sensing electric fields. The ampullae may also allow the shark to detect changes in water temperature. Each ampulla is a bundle of sensory cells containing multiple nerve fibres.

Complementing this, afferent nerve fibres have been found that project to early visual areas such as the lingual gyrus from late in the dorsal (action) and ventral (perception) visual streams, as well as from the auditory association cortex. Feedback projections have also been observed in the opossum directly from the auditory association cortex to V1. This last observation currently highlights a point of controversy within the neuroscientific community. Sadato et al.

The tuber cinereum primarily constitutes nerve fibres travelling from the hypothalamus to the pituitary gland. Rather than providing signalling to the gland, many of these fibres actually function as the source of the substances released by the posterior lobe of this gland. Hence, the tuber cinereum functions as a rapid, high-concentration, hormonal route between the hypothalamus, median eminence, and pituitary gland, and from there into the general circulation.

The thalamic fasciculus is a component of the subthalamus. It is synonymous with field H1 of Forel. Nerve fibres form a tract containing cerebellothalamic (crossed) and pallidothalamic (uncrossed) fibres, that is insinuated between the thalamus and the zona incerta. The thalamic fasciculus consists of fibers from the ansa lenticularis and from the lenticular fasciculus, coming from different portions of the medial globus pallidus, before they jointly enter the ventral anterior nucleus of the thalamus.

A dermatome is an area of skin that is mainly supplied by afferent nerve fibres from the dorsal root of any given spinal nerve. There are 8 cervical nerves (C1 being an exception with no dermatome), 12 thoracic nerves, 5 lumbar nerves and 5 sacral nerves. Each of these nerves relays sensation (including pain) from a particular region of skin to the brain. A dermatome also refers to the part of an embryonic somite.

These neurons originate in an area of the developing head, the olfactory placode, that will give rise to the olfactory epithelium; they then pass through the cribriform plate, along with the fibres of the olfactory nerves, and into the rostral forebrain. From there they migrate to what will become the hypothalamus. Any problems with the development of the olfactory nerve fibres will prevent the progression of the GnRH releasing neurons towards the brain.

Diagram of a typical long bone showing both cortical (compact) and cancellous (spongy) bone. Haversian canals (sometimes canals of Havers, named after British physician Clopton Havers) are a series of microscopic tubes in the outermost region of bone called cortical bone that allow blood vessels and nerves to travel through them. Each haversian canal generally contains one or two capillaries and nerve fibres. The channels are formed by concentric layers called lamellae.

He found that the photoreceptor cells in the eye are interconnected in such a way that when one is stimulated, others nearby are depressed, thus enhancing the contrast in light patterns and sharpening the perception of shapes. Hartline thus built up a detailed understanding of the workings of individual photoreceptors and nerve fibres in the retina, and he showed how simple retinal mechanisms constitute vital steps in the integration of visual information.

In acidic solutions, complexes of hematein with metals (usually aluminium or iron, but also chromium, zirconium and several others) are used as biological stains. Aluminium-haematein (haemalum) is the "routine" stain for cell nuclei in sections of human and other animal tissues. Metal- haematein stains are available also for objects other than nuclei, including myelin sheaths of nerve fibres and various cytoplasmic organelles. The color of the stained objects depends on the salt used.

This arrangement means the brain, sub-pharyngeal ganglia and the circum-pharyngeal connectives form a nerve ring around the pharynx. The ventral nerve cord (formed by nerve cells and nerve fibres) begins at the sub- pharyngeal ganglia and extends below the alimentary canal to the most posterior body segment. The ventral nerve cord has a swelling, or ganglion, in each segment, i.e. a segmental ganglion, which occurs from the fifth to the last segment of the body.

Having entered Cambridge in 1935, Huxley graduated with a bachelor's degree in 1938. In 1939, Alan Lloyd Hodgkin returned from the US to take up a fellowship at Trinity College, and Huxley became one of his postgraduate students. Hodgkin was interested in the transmission of electrical signals along nerve fibres. Beginning in 1935 in Cambridge, he had made preliminary measurements on frog sciatic nerves suggesting that the accepted view of the nerve as a simple, elongated battery was flawed.

Blood vessels may be visualized within the endotendon running parallel to collagen fibres, with occasional branching transverse anastomoses. The internal tendon bulk is thought to contain no nerve fibres, but the epitenon and paratenon contain nerve endings, while Golgi tendon organs are present at the junction between tendon and muscle. Tendon length varies in all major groups and from person to person. Tendon length is, in practice, the deciding factor regarding actual and potential muscle size.

The high frequency vibrations coming from the device which is attached to the syringe inhibit the pain sensations coming from the needle. They may interfere with the signals of pain by closing the gate in the brain. The nerve fibres that are stimulated are the Ab fibres using pressure or vibration. Other receptors called meissner’s corpuscles in the deeper tissues and bone also contribute. This closes a ‘neural gate’ This decreases the patient’s feeling of pain.

The cord possesses one ganglion per segment, each of which produces lateral nerve fibres that run into the limbs. Many species possess a pair of rhabdomeric pigment-cup eyes, and numerous sensory bristles are on the head and body. Tardigrades all possess a buccopharyngeal apparatus (swallowing device made of muscles and spines that activates an inner jaw and begins digestion and movement along the throat and intestine) which, along with the claws, is used to differentiate species.

Early electrophysiological studies in frogs report that noxious mechanical, thermal and chemical stimuli excite primary afferent fibres with slowly conducting axons. There are two types of nerve fibre relevant to pain in amphibians. Group C nerve fibres are a type of sensory nerve fibre which lack a myelin sheath and have a small diameter, meaning they have a low nerve conduction velocity. The suffering associated with burns, toothaches, or crushing injury are caused by C fibre activity.

Thought processes are diffused and interconnected and are cognitive at a sensory level. The mind thinks at its deepest level in sense material, and the two hemispheres of the brain deal with different kinds of thought.Thomas R Blakeslee, The right brain: a new understanding of the unconscious mind and its creative power, Macmillan, London, 1980. The brain is divided into two hemispheres and a thick bundle of nerve fibres enable these two halves to communicate with each other.

There, she and her husband collaborated on peripheral nerve regeneration at the Georgian Institute of Experimental Medicine in Sukhumi from 1940-1945. After the war, Lubińska's research continued in the realm of the peripheral nervous system. From 1945 to her retirement in 1982, she studied neural structure and physiology, especially axoplasmic transport, and showed that axoplasmic transport could be bidirectional."Axoplasmic streaming in regenerating and in normal nerve fibres" (1964 Progress in Brain Research Vol. 13).

A neurological disease refers to any ailment of the central nervous system, including abnormalities of the brain, spinal cord and other connecting nerve fibres.. Where millions of people are affected by neurological diseases on a worldwide scale,. it has been identified that the number of different types of neurological diseases exceeds six hundred,. any of which an individual can incur. Some of the most prevalent types include Alzheimer's disease, cerebral palsy, epilepsy, Parkinson's disease and stroke.

He described an extremely dense and intricate network, composed of a web of intertwined branches of axons coming from different cell layers ("diffuse nervous network"). This network structure, which emerges from the axons, is essentially different from that hypothesized by Gerlach. It was the main organ of the central nervous system according to Golgi. Thus, Golgi presented the reticular theory which states that the brain is a single network of nerve fibres, and not of discrete cells.

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 horseshoe crab has traditionally been used in investigations into the eye, because it has relatively large ommatidia with large nerve fibres (making them easy to experiment on). It also falls in the stem group of the chelicerates; its eyes are believed to represent the ancestral condition because they have changed so little over evolutionary time. Indeed, the horseshoe crabs are often considered to be living fossils. Most other living chelicerates have lost their lateral compound eyes, evolving simple eyes in their place.

She showed that the protein DLK1 helps these axons to find their way, through a series of specific chemical signals. At the receiver end, Jin has shown that the quality of neurons is evaluated by the EBAX-1 and hsp90, which serve to identify defects and fix any flaws. Jin has investigated the nerve fibres involved with neuroregeneration. During her investigations, she identified a new genetic pathway – the piwi-interacting RNA (piRNA) – the is involved with the rehabilitation of neuron damage.

Also, she discovered that when two nerve fibres are close in proximity, the activity of a single nerve fibre can generate activity in a nearby nerve fibre. Arvanitaki and her husband Chalazonitis both explored the methodology of electrophysiological activity of the nervous system of the sea hare genus Aplysia. In 1955, Arvanitaki and Chalazonitis as well as Ladislav Tauc created the first intracellular recordings of large neurons of the California sea hare. Arvanitaki's and Chalazonitis' explored photoexcitability of certain neurons.

Macartney discovered the fibrous texture of the white substance in the brain, and the connection between the subcortical nerve fibres and the grey matter of the cerebral hemispheres. He gave, too, the first satisfactory account of rumination in the herbivora, and he discovered numerous glandular appendages in the digestive organs of mammals, especially of rodents. As one of Warburton's advisers and as a practical anatomist of great experience in teaching, he had much to do in shaping the Anatomy Act of 1832.

The exact position of the electrode tip within the nerve is then adjusted in minute steps until the electrode discriminates impulses of the neural system of interest. A unique feature and a significant strength of the microneurography method is that subjects are fully awake and able to cooperate in tests requiring mental attention, while impulses in a representative nerve fibre or set of nerve fibres are recorded, e.g. when cutaneous sense organs are stimulated or subjects perform voluntary precision movements.

Nociception: The reflex arc of a dog with a pin in her paw. Note there is no communication to the brain, but the paw is withdrawn by nervous impulses generated by the spinal cord. There is no conscious interpretation of the stimulus by the dog involved in the reflex itself. In vertebrates, nociceptive responses involve the transmission of a signal along a chain of nerve fibres from the site of a noxious stimulus at the periphery, to the spinal cord.

Eimer asserted that his interpretation was consistent with the common knowledge of his time. In his publication he noted that the extreme density of highly sensitive nerve fibres is the cause of a light blow to the snout being able to kill the mole instantly. Roughly 130 years after Eimer's discovery, Catania and colleagues recorded in 2004 striking behavioural evidence in favour of his conclusions, using a high-speed camera. Moles with the help of their Eimer's organs may be perfectly poised to detect seismic wave vibrations.

After some time new grass replaces the burnt grass, and the field acquires again the ability for igniting. This is an example of an excitation wave. There are a great deal of other natural objects that are also considered among autowave processes: oscillatory chemical reactions in active media (e.g., Belousov–Zhabotinsky reaction), the spread of excitation pulses along nerve fibres, wave chemical signalling in the colonies of certain microorganisms, autowaves in ferroelectric and semiconductor films, population waves, spread of epidemics and of genes, and many other phenomena.

This forms an unbroken tube from the surface of the spinal cord to the level where the axon synapses with its muscle fibres, or ends in sensory receptors. The endoneurium consists of an inner sleeve of material called the glycocalyx and an outer, delicate, meshwork of collagen fibres. Nerves are bundled and often travel along with blood vessels, since the neurons of a nerve have fairly high energy requirements. Within the endoneurium, the individual nerve fibres are surrounded by a low-protein liquid called endoneurial fluid.

The inputs from these other areas of the brain probably play a role in sound localization. In order to understand in more detail the specific functions of the cochlear nuclei it is first necessary to understand the way sound information is represented by the fibers of the auditory nerve. Briefly, there are around 30,000 auditory nerve fibres in each of the two auditory nerves. Each fiber is an axon of a spiral ganglion cell that represents a particular frequency of sound, and a particular range of loudness.

The inferonasal retina are related to the anterior portion of the optic chiasm whereas superonasal retinal fibers are related to the posterior portion of the optic chiasm. The partial crossing over of optic nerve fibres at the optic chiasm allows the visual cortex to receive the same hemispheric visual field from both eyes. Superimposing and processing these monocular visual signals allow the visual cortex to generate binocular and stereoscopic vision. The net result is that the right cerebral hemisphere processes left visual hemifield, and the left cerebral hemisphere processes the right visual hemifield.

The optic nerve is a bundle of nerve fibres which carry messages from the eye to the relevant parts of the brain. Like mammals, birds have a small blind spot without photoreceptors at the optic disc, under which the optic nerve and blood vessels join the eye. The pecten is a poorly understood body consisting of folded tissue which projects from the retina. It is well supplied with blood vessels and appears to keep the retina supplied with nutrients, and may also shade the retina from dazzling light or aid in detecting moving objects.

Target selection is the process by which axons (nerve fibres) selectively target other cells for synapse formation. Synapses are structures which enable electrical or chemical signals to pass between nerves. Once thought to be more of a random process, it is now believed the first axons to grow outwards in the developing nervous system grow along specific and reproducible routes to form their connections. Typically these early pathways are forged by groups of axons that grow in poorly bundled ribbons that becomes thickened over time as follower axons are added into each tract.

In 1947 he got an opportunity to join Prof Hermann Rein at the Physiological Institute, Göttingen, to study the electrical activity of nerve fibres. He was rather isolated in a department mainly working on the control of the circulation in mammals, so he was glad to be invited by Alexander von Muralt to work in the Theodor Kocher Institute in Bern. In Bern, Robert Stämpfli taught him to dissect single myelinated fibres. He made four important publications in German on frog nervous system (myelinated neurons) during his research training.

Nerve fibres in the corticospinal tract originate from pyramidal cells in layer V of the cerebral cortex. Fibres arise from the primary motor cortex (about 30%), supplementary motor area and the premotor cortex (together also about 30%), and the somatosensory cortex, parietal lobe, and cingulate gyrus supplies the rest. The cells have their bodies in the cerebral cortex, and the axons form the bulk of the pyramidal tracts. The nerve axons travel from the cortex through the posterior limb of internal capsule, through the cerebral peduncle and into the brainstem and anterior medulla oblongata.

Studies of fruit fly mushroom bodies have been particularly important for understanding the genetic basis of mushroom body functioning, since their genome has been sequenced and a vast number of tools to manipulate their gene expression exist. In the insect brain, the peduncles of the mushroom bodies extend through the midbrain. They are mainly composed of the long, densely packed nerve fibres of the Kenyon cells, the intrinsic neurons of the mushroom bodies. These cells have been found in the mushroom bodies of all species that have been investigated, though their number varies.

Virginia–Maryland Regional College of Veterinary Medicine From closest to farthest from the vitreous body: # Inner limiting membrane – basement membrane elaborated by Müller cells. # Nerve fibre layer – axons of the ganglion cell bodies (note that a thin layer of Müller cell footplates exists between this layer and the inner limiting membrane). # Ganglion cell layer – contains nuclei of ganglion cells, the axons of which become the optic nerve fibres, and some displaced amacrine cells. # Inner plexiform layer – contains the synapse between the bipolar cell axons and the dendrites of the ganglion and amacrine cells.

Gargalesis reactions refer to a laughter-provoking feeling caused by a harsher, deeper pressure, stroked across the skin in various regions of the body. These reactions are thought to be limited to humans and other primates, although some research has indicated that rats can also be tickled in this way. A German study also indicates that the gargalesis type of tickle triggers a defense mechanism for humans in the hypothalamus conveying submissiveness or fleeing from danger. It appears that the tickle sensation involves signals from nerve fibres associated with both pain and touch.

Tickle may also depend on nerve fibres associated with the sense of touch. When circulation is severed in a limb, the response to touch and tickle are lost prior to the loss of pain sensation. It might be tempting to speculate that areas of the skin that are the most sensitive to touch would also be the most ticklish, but this does not seem to be the case. While the palm of the hand is far more sensitive to touch, most people find that the soles of their feet are the most ticklish.

Because of the large synaptic contact from the auditory nerve fibres, the output pattern from the bushy cell is almost the same as the auditory nerve input. Projections from the globular bushy cells extend to the superior olive on both sides of the brainstem where they give input to the bipolar neurons. The superior olive is an area seen to be of importance in the processing of binaural signals. Projections from the spherical bushy cells give excitatory input to the lateral and medial parts of the superior olive.

Indeed, JZ Young, Professor of Anatomy, 1945–74, discovered and was the first to investigate the squid giant axon. Young's work on squid giant axons was utilized by Andrew Huxley and Alan Hodgkin who in 1963 received the Nobel Prize for their work on the conduction of action potentials along nerve fibres. To achieve this, they developed a voltage-clamp technique to demonstrate that impulse transmission relied upon the selective permeability of the nerve fibre membrane to particular ions. This ground- breaking advance laid the foundations for much of modern-day electrophysiology.

Mechano- responsive nociceptors have been shown in studies to respond to mostly pain, and mechano-insensitive receptors respond mostly to itch induced by histamine. However, it does not explain mechanically induced itch or when itch is produced without a flare reaction which involves no histamine. Therefore, it is possible that pruritoceptive nerve fibres have different classes of fibres, which is unclear in current research. Studies have been done to show that itch receptors are found only on the top two skin layers, the epidermis and the epidermal/dermal transition layers.

The hypoglossal nerve plays an important role in controlling movements of the tongue. In 1998, one research team used the size of the hypoglossal canal in the base of fossil skulls in an attempt to estimate the relative number of nerve fibres, claiming on this basis that Middle Pleistocene hominins and Neanderthals had more fine-tuned tongue control than either australopithecines or apes. Subsequently, however, it was demonstrated that hypoglossal canal size and nerve sizes are not correlated, and it is now accepted that such evidence is uninformative about the timing of human speech evolution.

In 1894 at the age of 26, he published the influential Atlas of the Human Brain and the Course of the Nerve-Fibres, which was published in German, English, French, Russian, and in 1896 in Polish. The Polish edition was dedicated "To the memory of a noble man and an eminent physician Profesor Tytus Chałubiński author dedicates this work." The atlas was based on long-exposure photographs of fresh brain sections (up to 10 minutes for flat and 30 minutes for uneven surfaces, by means of small diaphragms). These studies were done in Berlin under Professor Emanuel Mendel.

The Oculocardiac reflex, also known as Aschner phenomenon, Aschner reflex, or Aschner–Dagnini reflex, is a decrease in pulse rate associated with traction applied to extraocular muscles and/or compression of the eyeball. The reflex is mediated by nerve connections between the ophthalmic branch of the trigeminal cranial nerve via the ciliary ganglion, and the vagus nerve of the parasympathetic nervous system. Nerve fibres from the maxillary and mandibular divisions of the trigeminal nerve have also been documented. These afferents synapse with the visceral motor nucleus of the vagus nerve, located in the reticular formation of the brain stem.

Eimer recognized the importance of the mole's nose to its behaviour. He stated in 1871: "The mole's snout must be the seat of an extraordinarily well developed sense of touch because it replaces almost entirely the animal's sense of face, constituting its only guide on its paths underground." He estimated that the nose of the European mole was covered with more than 5,000 Eimer's organs, which were invested with 105,000 nerve fibres. He took the abundance of sensory innervation (stimulate a nerve or muscle) to affirm his contention that the nose's touch must represent the moles dominant facial sense.

The epinephrine and norepinephrine strike the beta receptors of the heart, which feeds the heart's sympathetic nerve fibres to increase the strength of heart muscle contraction; as a result, more blood gets circulated, increasing the heart rate and respiratory rate. The sympathetic nervous system also stimulates the skeletal system and muscular system to pump more blood to those areas to handle the acute stress. Simultaneously, the sympathetic nervous system inhibits the digestive system and the urinary system to optimise blood flow to the heart, lungs, and skeletal muscles. This plays a role in the alarm reaction stage.

The optic recess - marks the inferior end of the lamina terminalis, with the optic chiasm forming the immediately adjacent floor. The portion of the floor immediately posterior of the optic chiasm distends inferiorly, and slightly anteriorly, to form a funnel (the infundibulum); the recess leading to the funnel is known as the infundibular recess. The border of the funnel is the tuber cinereum, which constitutes a bundle of nerve fibres from the hypothalamus. The funnel ends in the posterior lobe of the pituitary gland, which is thus neurally connected to the hypothalamus via the tuber cinereum.

In 1939, Yngve Zotterman of the Karolinska Institute studied the knismesis type of tickle in cats, by measuring the action potentials generated in the nerve fibres while lightly stroking the skin with a piece of cotton wool. Zotterman found that the "tickling" sensation depended, in part, on the nerves that generate pain. Further studies have discovered that when the pain nerves are severed by surgeons, in an effort to reduce intractable pain, the tickle response is also diminished. However, in some patients that have lost pain sensation due to spinal cord injury, some aspects of the tickle response do remain.

A nerve is an enclosed, cable-like bundle of nerve fibres called axons, in the peripheral nervous system. A nerve transmits electrical impulses and is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the electrochemical nerve impulses called action potentials that are transmitted along each of the axons to peripheral organs or, in the case of sensory nerves, from the periphery back to the central nervous system. Each axon within the nerve is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin.

Cavities of human body Human anatomy is the study of the shape and form of the human body. The human body has four limbs (two arms and two legs), a head and a neck which connect to the torso. The body's shape is determined by a strong skeleton made of bone and cartilage, surrounded by fat, muscle, connective tissue, organs, and other structures. The spine at the back of the skeleton contains the flexible vertebral column which surrounds the spinal cord, which is a collection of nerve fibres connecting the brain to the rest of the body.

Museo di storia naturale e del territorio dell'Università di Pisa The anatomy of finless porpoises has been relatively well studied, compared with that of some other cetacean species. For example, the tubercles along the dorsal ridge are known to contain numerous nerve endings that may possess a sensory function. The auditory system also appears well-developed, with numerous large nerve fibres specialised for rapid communication between the ears and the brain. On the other hand, sight is relatively poor, with a reduced lens and a limited number of fibres in the optic nerve and to the muscles moving the eyes.

The anatomy of finless porpoises has been relatively well studied, compared with that of some other cetacean species. The tubercles along the dorsal ridge are known to contain numerous nerve endings is used as a sensory function. The auditory system also appears well-developed, with numerous nerve fibres specialised for rapid communication between the ears and the brain. Sight is relatively poor, however, due to the overall cloudiness of the Yangtze River; they have a reduced lens and a limited number of fibres in the optic nerve and to the muscles moving the eyes compared to the Indo-pacific finless porpoise.

Large datasets representing normal responses to sensory tests have been established to quantitate deviation from the mean and allow comparison with normal patients. It is thought that a detailed evaluation of somatosensory function may be useful in identifying subtypes of pain and as a potential tool to identify asymptomatic neuropathy, which may represent up to 50% of total people with neuropathy (or loss of the nerve fibres). In clinical use, it is often combined with other tests such as clinical electrophysiology. In research settings it is increasingly applied in combination with advanced imaging such as fMRI, epidermis "nerve" biopsies and microneurography to classify subtypes of painful disorders.

Adult Lepidoptera have two pairs of membranous wings covered, usually completely, by minute scales. A wing consists of an upper and lower membrane which are connected by minute fibres and strengthened by a system of thickened hollow ribs, popularly but incorrectly referred to as "veins", as they may also contain tracheae, nerve fibres, and blood vessels.. The membranes are covered with minute scales which have jagged ends or hairs and are attached by hooks. The wings are moved by the rapid muscular contraction and expansion of the thorax. The wings arise from the meso- and meta-thoracic segments and are similar in size in the basal groups.

In both cases the sixth cranial nerve nucleus and nerve was absent, and the lateral rectus muscle was innervated by the inferior division of the third or oculomotor nerve. This misdirection of nerve fibres results in opposing muscles being innervated by the same nerve. Thus, on attempted abduction, stimulation of the lateral rectus via the oculomotor nerve will be accompanied by stimulation of the opposing medial rectus via the same nerve; a muscle which works to adduct the eye. Thus, co-contraction of the muscles takes place, limiting the amount of movement achievable and also resulting in retraction of the eye into the socket.

Young has also been called the founder of physiological optics. In 1793 he explained the mode in which the eye accommodates itself to vision at different distances as depending on change of the curvature of the crystalline lens; in 1801 he was the first to describe astigmatism; and in his lectures he presented the hypothesis, afterwards developed by Hermann von Helmholtz, (the Young–Helmholtz theory), that colour perception depends on the presence in the retina of three kinds of nerve fibres. This foreshadowed the modern understanding of colour vision, in particular the finding that the eye does indeed have three colour receptors which are sensitive to different wavelength ranges.

Mutations in this gene have been associated with optic atrophy type 1, which is a dominantly inherited optic neuropathy resulting in progressive loss of visual acuity, leading in many cases to legal blindness. Dominant optic atrophy (DOA) in particular has been traced to mutations in the GTPase domain of OPA1, leading to sensorineural hearing loss, ataxia, sensorimotor neuropathy, progressive external ophthalmoplegia, and mitochondrial myopathy. As the mutations can lead to degeneration of auditory nerve fibres, cochlear implants provide a therapeutic means to improve hearing thresholds and speech perception in patients with OPA1-derived hearing loss. Mitochondrial fusion involving OPA1 and MFN2 may be associated with Parkinson's disease.

This contradicts the polyvagal description of the dorsal motor nucleus as being "phylogenetically older" than the nucleus ambiguus, or of the latter being unique to mammals. In addition, recent findings in lungfish suggest that myelinated vagus nerve fibres leading from the nucleus ambiguus to the heart long precede the evolution of mammals. In polyvagal theory the term vagal tone is equated with respiratory sinus arrhythmia (RSA), which is suggested to be linked to dimensions of psychopathology. A number of research studies have evaluated RSA responses across a range of dimensions of psychopathology, but a comprehensive meta- analysis has shown that no clinically meaningful relation can be found between psychopathology and RSA reactivity.

The present understanding of pain in babies is largely due to the recognition that the fetal and newborn unmyelinated nerve fibres are capable of relaying information, albeit slower than would be the case with myelinated fibres. At birth a baby has developed the neural pathways for nociception and for experiencing pain, but the pain responses are an immature version of that of an adult. There are a number of differences in both nerve structure and in the quality and extent of nerve response which are considered to be pertinent to understanding neonatal pain. The nerves of young babies respond more readily to noxious stimuli, with a lower threshold to stimulation, than those of adults.

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.

Diffusion tensor imaging of the brain showing the right and left arcuate fasciculus (Raf & Laf), the right and left superior longitudinal fasciculus (Rslf & Lslf), and tapetum of corpus callosum (Ta). Disconnection syndrome is a general term for a collection of neurological symptoms caused -- via lesions to associational or commissural nerve fibres -- by damage to the white matter axons of communication pathways in the cerebrum (not to be confused with the cerebellum), independent of any lesions to the cortex. The behavioral effects of such disconnections are relatively predictable in adults. Disconnection syndromes usually reflect circumstances where regions A and B still have their functional specializations except in domains that depend on the interconnections between the two regions.

Continuing earlier studies of Keith Lucas, he used a capillary electrometer and cathode ray tube to amplify the signals produced by the nervous system and was able to record the electrical discharge of single nerve fibres under physical stimulus. (It seems he used frogs in his experiments) An accidental discovery by Adrian in 1928 proved the presence of electricity within nerve cells. Adrian said, > I had arranged electrodes on the optic nerve of a toad in connection with > some experiments on the retina. The room was nearly dark and I was puzzled > to hear repeated noises in the loudspeaker attached to the amplifier, noises > indicating that a great deal of impulse activity was going on.

In 1994, Neil Sachse and Dawn Ferrett founded an organisation to raise funds for research into the treatment of spinal cord injury. Originally known as the Spinal Research Fund of Australia Incorporated, it was renamed the Neil Sachse Foundation. Since 1994, it has raised over $2 million which has funded a research project at Flinders University that proved that nerve fibres in the spine can regenerate past the site of the injury and return some function. In 2009, in recognition of his tireless work and dedication, Neil was awarded the "Premier's Award for Outstanding Community Achievement in South Australia" at an Awards Ceremony run by the Australia Day Council of SA at Government House.

The optic foramen is the opening to the optic canal. The canal is located in the sphenoid bone; it is bounded medially by the body of the sphenoid and laterally by the lesser wing of the sphenoid. The superior surface of the sphenoid bone is bounded behind by a ridge, which forms the anterior border of a narrow, transverse groove, the chiasmatic groove (optic groove), above and behind which lies the optic chiasma; the groove ends on either side in the optic foramen, which transmits the optic nerve and ophthalmic artery (with accompanying sympathetic nerve fibres) into the orbital cavity. Compared to the optic nerve, the ophthalmic artery is located inferolaterally within the canal.

Natural shapes of rat's mystacial pad vibrissae are well approximated by pieces of the Euler spiral. When all these pieces for a single rat are assembled together, they span an interval extending from one coiled domain of the Euler spiral to the other. Rats and mice are considered to be "whisker specialists", but marine mammals may make even greater investment in their vibrissal sensory system. Seal whiskers, which are similarly arrayed across the mystacial region, are each served by around 10 times as many nerve fibres as those in rats and mice, so that the total number of nerve cells innervating the mystacial vibrissae of a seal has been estimated to be in excess of 300,000.

Rabbani has been working to improve the condition of economically deprived people of Bangladesh through innovating low cost and easily accessible technologies. He had three major innovations cited by Bangladesh Academy of Sciences as, "A simple and low cost method to destroy diarrhoeal germs in water using solar radiation; Surface water free of Arsenic that can be made drinkable; a localised electrical impedance technique named ‘Focused Impedance Method (FIM), having the potential to study, diagnose or characterize medical conditions including lung, stomach and vascular functions and some cancers; a nerve conduction measurement technique ‘Distribution of F-latency, (DFL), that can give inner profile of conduction velocity of motor nerve fibres in a nerve trunk, for which no clinically suitable method existed before".

The camera eyes of vertebrates (left) and cephalopods (right) developed independently and are wired differently; for instance, optic nerve fibres reach the vertebrate retina from the front, creating a blind spot. One of the best-known examples of convergent evolution is the camera eye of cephalopods (such as squid and octopus), vertebrates (including mammals) and cnidaria (such as jellyfish). Their last common ancestor had at most a simple photoreceptive spot, but a range of processes led to the progressive refinement of camera eyes — with one sharp difference: the cephalopod eye is "wired" in the opposite direction, with blood and nerve vessels entering from the back of the retina, rather than the front as in vertebrates. As a result, cephalopods lack a blind spot.

Mosby's Dictionary of Medicine, Nursing & Health Professions defines the LGN as "one of two elevations of the lateral posterior thalamus receiving visual impulses from the retina via the optic nerves and tracts and relaying the impulses to the calcarine (visual) cortex". What is seen in the left and right visual field is taken in by each eye and brought back to the optic disc via the nerve fibres of the retina. From the optic disc, visual information travels through the optic nerve and into the optic chiasm. Visual information then enters the optic tract and travels to four different areas of the brain including the superior colliculus, pretectum of the mid brain, the suprachiasmatic nucleus of the hypothalamus, and the lateral geniculate nucleus (LGN).

The BBC describes the research published in the peer-reviewed science journal PLoS ONE: :"A research team led by Hao Lei of the Chinese Academy of Sciences in Wuhan carried out brain scans of 35 men and women aged between 14 and 21. Seventeen of them were classed as having Internet addiction disorder (IAD) on the basis of answering yes to questions such as, “Have you repeatedly made unsuccessful efforts to control, cut back or stop Internet use?” Specialised MRI brain scans showed changes in the white matter of the brain—the part that contains nerve fibres—in those classed as being web addicts, compared with non-addicts. Furthermore, the study says, "We provided evidences demonstrating the multiple structural changes of the brain in IAD subjects.

The optic disc, a part of the retina sometimes called "the blind spot" because it lacks photoreceptors, is located at the optic papilla, where the optic-nerve fibres leave the eye. It appears as an oval white area of 3 mm². Temporal (in the direction of the temples) to this disc is the macula, at whose centre is the fovea, a pit that is responsible for our sharp central vision but is actually less sensitive to light because of its lack of rods. Human and non-human primates possess one fovea, as opposed to certain bird species, such as hawks, who are bifoviate, and dogs and cats, who possess no fovea but a central band known as the visual streak.

The lateral side of the ventricle is marked by a sulcus - the hypothalamic sulcus - from the inferior side of the interventricular foramina to the anterior side of the cerebral aqueduct. The lateral border posterior/superior of the sulcus constitutes the thalamus, while anterior/inferior of the sulcus it constitutes the hypothalamus. The interthalamic adhesion usually tunnels through the thalamic portion of the ventricle, joining together the left and right halves of the thalamus, although it is sometimes absent, or split into more than one tunnel through the ventricle; it is currently unknown whether any nerve fibres pass between the left and right thalamus via the adhesion (it has more resemblance to a herniation than a commissure). The posterior border of the ventricle primarily constitutes the epithalamus.

The menisci are the other intra-articular structures that help to stabilise the joint and help to distribute load evenly across the surfaces; these are crescent-shaped discs of cartilage facing each other from side to side across the joint. They are thicker at the outside and with a thin inner aspect and they also have nerve fibres that help to tell the brain how much load is getting transmitted through the joint. The medial (inside) meniscus is often damaged with a long-standing cruciate ligament rupture because it is firmly attached to the tibia and gets crushed during abnormal cranial movement of the tibia. The lateral (outside) meniscus is more firmly attached to the femur and does not get crushed.

The LOCS (originating from both the intrinsic and shell neurons) contains unmyelinated fibres that synapse with the dendrites of the Type I spiral ganglion cells projecting to the inner hair cells. While the intrinsic LOCS neurons tend to be small (~10 to 15 µm in diameter), and the shell OC neurons are larger (~25 µm in diameter), it is the intrinsic OC neurons that possess the larger axons (0.77 µm compared to 0.37 µm diameter for shell neurons). In contrast, the MOCS contains myelinated nerve fibres which innervate the outer hair cells directly. Although both the LOCS and MOCS contain crossed (contralateral) and uncrossed (ipsilateral) fibres, in most mammalian species the majority of LOCS fibres project to the ipsilateral cochlea, whilst the majority of the MOCS fibres project to the contralateral cochlea.

This is mainly due to numerous observations that large axonal accumulations are invariably seen in affected neurons, and that genes known to play a role in the familial forms of these diseases also have purported roles in normal axonal transport. However, there is little direct evidence for involvement of axonal transport in the latter diseases, and other mechanisms (such as direct synaptotoxicity) may be more relevant. Arrest of axoplasmic flow at the edge of ischemic area in vascular retinopathies lead to swelling of nerve fibres which give rise to soft exudates or cotton-wool patches. Since the axon depends on axoplasmic transport for vital proteins and materials, injury such as diffuse axonal injury that interrupts the transport will cause the distal axon to degenerate in a process called Wallerian degeneration.

If the post-synaptic cell is a sensory neuron, then an increased firing rate in that neuron will transmit the signal to the central nervous system for integration. Whereas, if the post- synaptic cell is a connective pillar cell or a vascular smooth muscle cell, then the serotonin will cause vasoconstriction and previously unused lamellae will be recruited through recruitment of more capillary beds, and the total surface area for gas exchange per lamella will be increased. In fish, the hypoxic signal is carried up to the brain for processing by the glossopharyngeal (cranial nerve IX) and vagus (cranial nerve X) nerves. The first branchial arch is innervated by the glossopharyngeal nerve (cranial nerve IX); however all four arches are innervated by the vagus nerve (cranial nerve X). Both the glossopharyngeal and vagus nerves carry sensory nerve fibres into the brain and central nervous system.

In this condition, they found that the N1 potential evoked by click stimuli was enhanced during a period of MOC stimulation. This finding has been confirmed using both electrical stimulation (Dolan and Nuttall, 1988; Winslow and Sachs, 1987) and acoustic activation (Kawase et al., 1993, Kawase and Liberman, 1993) of the mammalian MOCS. Winslow and Sachs (1987) found that stimulating the OCB: “...enables auditory nerve fibres to signal changes in tone level with changes in discharge rate at lower signal-to-noise ratios than would be possible otherwise.” (Page 2002) One interpretation of these findings is that MOC stimulation selectively reduces the auditory nerve’s response to constant background noise, allowing a greater response to a transient sound. In this way, MOC stimulation would reduce the effect of both suppressive and adaptive masking, and for this reason, the process has been referred to as “unmasking” or “antimasking” (Kawase et al.

The superior part of the posterior border constitutes the habenular commissure, while more centrally it the pineal gland, which regulates sleep and reacts to light levels. Caudal of the pineal gland is the posterior commissure; nerve fibres reach the posterior commissure from the adjacent midbrain, but their onward connection is currently uncertain. The commissures create concavity to the shape of the posterior ventricle border, causing the suprapineal recess above the habenular, and the deeper pineal recess between the habenular and posterior commissures; the recesses being so-named due to the pineal recess being bordered by the pineal gland. The hypothalmic portion of the third ventricle (upper right), and surrounding structures The anterior wall of the ventricle forms the lamina terminalis, within which the vascular organ monitors and regulates the osmotic concentration of the blood; the cerebrum lies beyond the lamina, and causes it to have a slightly concave shape.

There he met Rafael Lorente de Nó and Kenneth Stewart Cole with whom he ended up publishing a paper. During that year he also spent time at the Woods Hole Marine Biological Laboratory where he was introduced to the squid giant axon, which ended up being the model system with which he conducted most of the research that eventually led to his Nobel Prize. In spring 1938 he visited Joseph Erlanger at Washington University in St. Louis who told him he would take Hodgkin's local circuit theory of nerve impulse propagation seriously if he could show that altering the resistance of the fluid outside a nerve fibre made a difference to the velocity of nerve impulse conduction. Working with single nerve fibres from shore crabs and squids, he showed that the conduction rate was much faster in sea water than in oil, providing strong evidence for the local circuit theory.

With Seddon's classification of nerve injuries, it is often tough to identify whether a particular nerve injury is neurotmesis, or axonotmesis, which has damage to the nerve fibres but preservation of the nerve trunk. Due to the damage involved in both of these conditions they will both show paralysis of muscles that are supplied by nerves below the site of the lesion, and will have sensory deficits in accordance with the individual nerves that are damaged. The only way to know for sure if a nerve injury is in fact neurotmesis is to allow for the normal progression of nerve regeneration to take place (nerves regenerate at a rate of approximately 2–4 mm/day proximal to the lesion), and if, after that time, there is still profound muscle paralysis and degeneration in these areas, then it is likely to have been a neurotmesis injury. Neurotmesis is diagnosed through clinical evaluation of symptoms, physical evaluation, and other diagnostic studies.

The motor innervation of the gluteus maximus muscle is performed by the inferior gluteal nerve (a branch nerve of the sacral plexus) and extends from the pelvis to the gluteal region, then traverses the greater sciatic foramen (opening) from behind and to the middle to then join the sciatic nerve. The inferior gluteal nerve divides into three (3) collateral branches: (i) the gluteus branch, (ii) the perineal branch, and (iii) the femoral branch. The first ramification — the gluteus branch — is a branch nerve that is very close to the emergence of the inferior gluteal nerve to the area, next to the inferior border of the pyramidalis muscle. As it arises, the inferior gluteal nerve then divides into four (4) or more fillets (bands of nerve fibres) that travel (in a crow's-foot configuration) between the gluteus maximus muscle and its (front) anterior fascia; the thickest nerve-bands are the superior-most and the inferior-most fillets.