True Vocal Folds The vocal folds, also known commonly as vocal cords



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  • True Vocal Folds

  • The vocal folds, also known commonly as vocal cords, are composed of twin infoldings of mucous membrane stretched horizontally across the larynx.

  • They vibrate, modulating the flow of air being expelled from the lungs during phonation.

  • Open during inhalation, closed when holding one's breath, and vibrating for speech or singing; the folds are controlled via the vagus nerve. They are white because of scant blood circulation.

  • Vocal Folds







  • Vocal Folds

  • The folds are located below the epiglottis.

  • The folds are located just above the trachea which travels from the lungs.

  • Food and drink does not pass through the folds but is instead taken through the esophagus. Both tubes are separated by the tongue and an automatic gag reflex. When food goes down through the folds and trachea it causes choking.

  • Folds in both sexes are within the larynx. They are attached at the back (side nearest the spinal cord) to the arytenoid cartilages, and at the front (side under the chin) to the thyroid cartilage. Men and women have different vocal fold sizes.

  • Vocal Folds

  • Their outer edges are attached to muscle in the larynx while their inner edges, or margins are free (the hole).

  • 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 vocal cord (the hole and the ligament itself) is the vestibular fold or false vocal fold, which has a small sac between its two folds.



  • False Vocal Folds

  • These are a pair of thick folds of mucous membrane that protect and sit slightly superior to the more delicate true folds.

  • They have minimal role in normal phonation.

  • The false folds are also called vestibular folds and ventricular folds.

  • False vocal folds, when surgically removed, can regenerate completely.



  • Extrinsic Laryngeal Muscles

  • infrahyoids-pull larynx down

  • suprahyoids-pull larynx upward

Intrinsic Muscles of the Larynx

Functions are:



  • Regulate openings of respiratory pathway.

  • Valves include: epiglottis

ventricular folds

vocal folds



  • Provide for movement of laryngeal

cartilages for speech.

    • Intrinsic Laryngeal Muscles

  • lateral cricoarytenoid (LCA) – adductor

  • interarytenoid (IA) – adductor; two bundles of muscle-transverse and oblique portions

  • posterior cricoarytenoid (PCA) – only abductor

  • cricothyroid (CT) – elongates the vocal folds






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