The movement of gas through the larynx, pharynx and mouth allows humans to speak, or phonate. Vocalization, or singing, in birds occurs via the syrinx, an organ located at the base of the trachea. The vibration of air flowing across the larynx (vocal cords), in humans, and the syrinx, in birds, results in sound. Because of this, gas movement is vital for communication purposes.
|
|
In singing, the modal register may also overlap part of the whistle register. A well trained singer or speaker can phonate two octaves or more within the modal register with consistent production, beauty of tone, dynamic variation, and vocal freedom. The modal register begins and ends in different places within the human voice. The placement of the modal register within the individual human voice is one of the key determining factors in identifying vocal type.
|
|
For patients with significant paralysis at 12 months post-onset, medialization thyroplasty may be suggested. This surgical procedure introduces a shim between the inner wall of the larynx and the soft tissue supporting the vocal fold. As a result, the paralyzed vocal fold is supported in a position closer to the midline of the glottis, and retains its ability to vibrate and phonate efficiently. In addition to medialization thyroplasty, arytenoid adduction can be performed to improve phonation results.
|
|
Vocal range is the range of pitches that a human voice can phonate. Its most common application is within the context of singing, where it is used as a defining characteristic for classifying singing voices into voice types. It is also a topic of study within linguistics, phonetics, and speech-language pathology, particularly in relation to the study of tonal languages and certain types of vocal disorders, although it has little practical application in terms of speech.
|
|
Typically by 6 months of age, all normally developing children will babble. However, infants with certain medical conditions or developmental delays may exhibit a delay or an absence of babbling. For example, infants who have had a tracheotomy typically do not babble because they are unable to phonate. Following decannulation, it has been found that these infants do produce more vocalizations, but the sounds or syllables are not as diverse as those found in typically developing infant's canonical babbling behaviour.
|
|
The whistle register is the highest phonational register, that in most singers begins above the soprano "high D" (D6 or 1174.6 Hz) and extends to about an octave above (D7 or 2349.3 Hz). It is created by using only the back of the vocal folds. The lower part of the whistle register may overlap the upper parts of the modal and falsetto registers, making it possible for singers to phonate these notes in different ways. However, fundamentally the whistle register is most commonly used to produce pitches above D6.
|
|
A diagram of ultrasonic signals emitted by a bat, and the echo from a nearby object As in all other tetrapods, mammals have a larynx that can quickly open and close to produce sounds, and a supralaryngeal vocal tract which filters this sound. The lungs and surrounding musculature provide the air stream and pressure required to phonate. The larynx controls the pitch and volume of sound, but the strength the lungs exert to exhale also contributes to volume. More primitive mammals, such as the echidna, can only hiss, as sound is achieved solely through exhaling through a partially closed larynx.
|
|
The modal voice is the usual register for speaking and singing, and the vast majority of both are done in this register. As pitch rises in this register, the vocal folds are lengthened, tension increases, and their edges become thinner. A well-trained singer or speaker can phonate two octaves or more in the modal register with consistent production, beauty of tone, dynamic variety, and vocal freedom. This is possible only if the singer or speaker avoids static laryngeal adjustments and allows the progression from the bottom to the top of the register to be a carefully graduated continuum of readjustments.
|
|
Other mammals phonate using vocal folds, as opposed to the vocal cords seen in birds and reptiles. The movement or tenseness of the vocal folds can result in many sounds such as purring and screaming. Mammals can change the position of the larynx, allowing them to breathe through the nose while swallowing through the mouth, and to form both oral and nasal sounds; nasal sounds, such as a dog whine, are generally soft sounds, and oral sounds, such as a dog bark, are generally loud. Beluga whale echolocation sounds Some mammals have a large larynx and thus a low-pitched voice, namely the hammer-headed bat (Hypsignathus monstrosus) where the larynx can take up the entirety of the thoracic cavity while pushing the lungs, heart, and trachea into the abdomen.
|
|