Vocal folds | |
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Laryngoscopic view of the vocal folds.
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Details | |
Precursor | Sixth pharyngeal arch |
System | Respiratory system |
Identifiers | |
Latin | plica vocalis |
MeSH | A04.329.364.737 |
Dorlands /Elsevier |
Vocal folds |
TA | A06.2.09.013 |
FMA | 55457 |
Anatomical terminology
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The vocal folds, also known commonly as vocal cords or voice reeds, are composed of twin infoldings of mucous membrane stretched horizontally, from back to front, across the larynx. They vibrate, modulating the flow of air being expelled from the lungs during phonation.
Open when breathing and vibrating for speech or singing, the folds are controlled via the vagus nerve.
The vocal folds are located within the larynx at the top of the trachea. They are attached posteriorly to the arytenoid cartilages, and anteriorly to the thyroid cartilage. They are part of the glottis which includes the rima glottidis. Their outer edges are attached to muscle in the larynx while their inner edges, or margins, are free forming the opening called the rima glottidis. They are constructed from epithelium, but they have a few muscle fibres in them, namely the vocalis muscle which tightens the front part of the ligament near to the thyroid cartilage. They are flat triangular bands and are pearly white in color. Above both sides of the glottis are the two vestibular folds or false vocal folds which have a small sac between them.
Situated above the larynx, the epiglottis acts as a flap which closes off the trachea during the act of swallowing to direct food into the esophagus. If food or liquid does enter the trachea and contacts the vocal folds it causes a cough reflex to expel the matter in order to prevent pulmonary aspiration.
Males and females have different vocal fold sizes. Adult male voices are usually lower pitched due to longer and thicker folds. The male vocal folds are between 1.75 cm and 2.5 cm (approx 0.75" to 1.0") in length, while female vocal folds are between 1.25 cm and 1.75 cm (approx 0.5" to 0.75") in length. The vocal folds of children are much shorter than those of adult males and females. The difference in vocal fold length and thickness between males and females causes a difference in vocal pitch. Additionally, genetic factors cause variations between members of the same sex, with males' and females' voices being categorized into voice types.