Logan Steele
The human vocal cords, also known as vocal folds, are folds of throat tissues that are key in creating sounds through vocalization. The vocal folds are multilayered structures, consisting of a muscle covered by a mucosal covering. The intrinsic laryngeal muscles act on the individual components of the larynx and control the shape of the rima glottidis, the opening between the vocal folds and the arytenoid cartilages. The muscles of the larynx can be divided into two groups: the external muscles and the internal muscles. The internal muscles, also known as the voice box muscles, form the body of the vocal folds themselves.
| Characteristics | Values |
|---|---|
| Vocal fold composition | Twin infoldings of 3 distinct tissues: an outer layer of flat cells (squamous epithelium), a gel-like layer (superficial lamina propria), and a mucous membrane |
| Vocal fold length | 12-24 mm |
| Vocal fold thickness | 3-5 mm |
| Male vocal fold length | 1.75-2.5 cm |
| Female vocal fold length | 1.25-1.75 cm |
| Vocal fold vibration | Controlled by the recurrent laryngeal branch of the vagus nerve |
| Vocal fold function | Provide a valve for the airway, vibrate to produce voice, and resist air pressure from the lungs |
| Vocal fold muscles | Cricothyroid, thyroarytenoid, interarytenoid, lateral cricoarytenoid, posterior cricoarytenoid, intrinsic laryngeal muscles, and extrinsic laryngeal muscles |
| Muscle function | The cricothyroid muscle lengthens the vocal folds and alters tone. The thyroarytenoid muscle forms the vocal folds, regulates tension, and lowers pitch. The interarytenoid and lateral cricoarytenoid muscles bring the vocal folds together. The posterior cricoarytenoid muscle opens the vocal folds. |
Explore related products
What You'll Learn
The thyroarytenoid muscle forms the vocal folds
The vocal folds, also known as the vocal cords, are multilayered structures that provide a valve for the airway and vibrate to produce the voice. The vocal folds are controlled by the recurrent laryngeal branch of the vagus nerve. They are composed of twin infoldings of mucous membrane stretched horizontally, from back to front, across the larynx. The vocal folds are made up of five layers, with the thyroarytenoid muscle forming the body of the vocal folds themselves.
The thyroarytenoid muscle is the deepest portion of the vocal fold, along with the vocalis muscle. The thyroarytenoid muscle helps close the glottis and regulate tension in the vocal fold during speaking and/or singing. The medial portion of this muscle is also called the vocalis muscle. The thyroarytenoid muscle also has a force to strengthen glottic closure.
The glottis is the space between the two vocal folds. When the vocal folds come together, the glottis closes; when they move apart, the glottis opens. The glottis opens and closes during vibration. The vocal folds vibrate, trapping and releasing air. Each release sends a little puff of air into the pharynx, and each puff of air is the beginning of a sound wave. The sound wave is enhanced as it travels through the pharynx; by the time it leaves the mouth, it sounds like a voice.
The thyroarytenoid muscle shortens the vocal folds by pulling the arytenoid (back) end of the vocal folds toward the thyroid (front) end. This shortens the vocal folds and bunches them up, which causes them to vibrate more slowly, thus lowering the pitch. The pitch of the voice is also affected by the length of the vocal cords. The thyroarytenoid muscle works in coordination with the lateral cricoarytenoid and interarytenoid muscles to bring the vocal folds together.
Complementary Muscles: The Key to Unlocking Optimal Performance
You may want to see also
Explore related products
Posterior cricoarytenoid muscles open the vocal folds
The posterior cricoarytenoid muscle is the only muscle of the larynx that abducts the vocal cords and, therefore, opens the rima glottidis. This muscle arises from the cricoid cartilage and inserts onto the arytenoid cartilage of the same side. It is innervated by the recurrent laryngeal nerve, a branch of the vagus nerve.
The posterior cricoarytenoid muscle is an antagonist to the lateral cricoarytenoid muscle, which acts to close the glottis and protect the airway. Contraction of the posterior cricoarytenoid muscle rotates the arytenoid cartilages and pulls them posterolaterally, thereby separating the vocal cords and assisting in lengthening them. This allows for the passage of air during inspiration and expiration, making the posterior cricoarytenoid muscle crucial for respiration.
The glottis is the space between the two vocal folds, and its opening and closing are essential for vibration and vocalisation. The vocal folds, also known as vocal cords, provide a valve for the airway and vibrate to produce the voice. When the vocal folds vibrate, they trap and release air, with each release sending a puff of air into the pharynx, initiating a sound wave.
The posterior cricoarytenoid muscle is the only muscle that opens the glottis, and its paralysis may lead to asphyxiation and death. This muscle also participates in the production of unvoiced sounds, such as letters that do not require vibration of the vocal cords. Injury to the recurrent laryngeal nerve can result in posterior cricoarytenoid muscle failure, which may occur during thyroidectomy operations or due to diseases affecting surrounding organs.
Dorsiflexion: Which Muscles Are Involved and Why It Matters
You may want to see also
Explore related products
Lateral cricoarytenoid muscles close the vocal folds
The vocal folds, also known as vocal cords, are multilayered structures that provide a valve for the airway and vibrate to produce the voice. The glottis is the space between the two vocal folds. Adduction occurs when the vocal folds come together to close the glottis, and abduction is the act of bringing the vocal folds apart to open the glottis for breathing.
The lateral cricoarytenoid muscles are the major adductors of the vocal folds. They originate from the arch of the cricoid cartilage and attach to the muscular process of the arytenoid cartilage. The contraction of the lateral cricoarytenoid muscle creates an inward rotation of the arytenoid on the cricoid, pulling the back ends of the arytenoid cartilages apart and pulling the front ends together, making the vocal folds come together. This closes the glottis and regulates tension in the vocal folds during speaking and/or singing. The lateral cricoarytenoid muscles also narrow the rima glottidis, modulating the tone and volume of speech.
The lateral cricoarytenoid muscles work in coordination with other muscles in the larynx, such as the interarytenoids and thyroarytenoids, to bring the vocal folds together and resist air pressure from the lungs. The muscles in the neck may also help provide stabilization or contribute to the squeezing effect.
The cricoarytenoid joint allows movement of the arytenoid on the cricoid ring for vocal fold abduction and adduction, controlled by the action of the intrinsic laryngeal musculature on the arytenoid. The intrinsic muscles act on the individual components of the larynx, controlling the shape of the rima glottidis (the opening between the vocal folds and the arytenoid cartilages), as well as the length and tension of the vocal folds.
Sauna Therapy: Muscle Relaxation and Recovery
You may want to see also
Explore related products
Interarytenoid muscles squeeze the vocal folds together
The vocal folds, also known as vocal cords, are multilayered structures that create sounds through vocalization. They are folds of throat tissues that vibrate and modulate the flow of air being expelled from the lungs during phonation. The vocal folds are controlled by the recurrent laryngeal branch of the vagus nerve.
The interarytenoid muscles are a part of the intrinsic laryngeal muscles, which act on the individual components of the larynx. They control the shape of the rima glottidis (the opening between the vocal folds and the arytenoid cartilages), and the length and tension of the vocal folds. The intrinsic muscles of the larynx (except the cricothyroid) are innervated by the inferior laryngeal nerve, which is a terminal branch of the recurrent laryngeal nerve.
The interarytenoid muscles squeeze the vocal folds together to provide medial compression for the vocal folds. In other words, the vocal folds squeeze together tighter to resist the air pressure from the lungs. There are two sets of interarytenoid muscles: the transverse arytenoids and the oblique arytenoids. These muscles bring the two arytenoid cartilages together, which results in glottal closure.
The interarytenoid muscles work in coordination with the thyroarytenoids and lateral cricoarytenoids to squeeze the vocal folds together more strongly. The muscles in the neck may also help provide stabilization or may help produce the squeezing effect. When the vocal folds are squeezed together for longer, the air builds up more pressure, resulting in a stronger explosion of air through the larynx.
Where Did My Muscle Go?
You may want to see also
Explore related products
Cricothyroid muscles lengthen the vocal folds
The vocal folds, also known as vocal cords, are multilayered structures that provide a valve for the airway and vibrate to produce the voice. The voice box, or larynx, and the vocal folds comprise the vibratory system of the voice mechanism. The vocal folds are controlled by the muscles in the neck and jaw that surround the larynx.
The cricothyroid muscles are the only tensor muscles of the larynx that aid with phonation. They pull the thyroid cartilage down and forward on its hinge, increasing the distance between the arytenoids and the thyroid notch (the Adam's Apple). This lengthens and tightens the vocal folds, causing them to vibrate faster and produce a higher pitch. The cricothyroid muscles are innervated by the superior laryngeal nerve, a branch of the vagus nerve.
The cricothyroid muscles work in conjunction with other muscles and cartilages to control the movement and tension of the vocal folds. For example, the thyroarytenoid muscles form the body of the vocal folds and help regulate tension during speaking and singing. They shorten the vocal folds by pulling the arytenoid (back) end towards the thyroid (front) end, causing the vocal folds to vibrate more slowly and produce a lower pitch.
The interarytenoid muscles also play a role in vocal fold movement. There are two sets of these muscles: the transverse arytenoids and the oblique arytenoids. They bring the two arytenoid cartilages together to provide medial compression for the vocal folds, allowing them to resist air pressure from the lungs.
The cricothyroid muscles, by lengthening and tightening the vocal folds, contribute to the overall function of the vocal mechanism. They work in coordination with other muscles and structures to enable phonation and the production of a range of pitches.
Hiking: Burning Muscle or Myth?
You may want to see also
Frequently asked questions
Vocal folds, also known as vocal cords, are folds of throat tissues that create sounds through vocalization.
The thyroarytenoid muscle forms the body of the vocal folds. The vocalis muscle, also known as the vocalis and thyroarytenoid muscles, make up the deepest portion of the vocal folds.
The lateral cricoarytenoid, interarytenoid, and posterior cricoarytenoid muscles are involved in the creation of vocal folds. The lateral and interarytenoid muscles close the glottis by pulling the arytenoid cartilages together, while the posterior cricoarytenoid opens the glottis by pulling the cartilages apart.
The vocalis muscle helps to close the glottis and regulate tension in the vocal folds during speaking and/or singing.
The vocal folds vibrate, modulating the flow of air being expelled from the lungs during phonation. The length of the vocal folds affects the pitch of the voice.
