Victor Forge
The larynx is a flexible structure that houses the vocal cords and is responsible for producing phonation. The vocal cords, also known as the vocal folds, are made of muscles covered by a thin layer of mucosa. The intrinsic muscles of the larynx control the shape of the opening between the vocal folds and the arytenoid cartilages, as well as the length and tension of the vocal folds. One of these intrinsic muscles, the vocalis muscle, runs along the vocal ligament within the folds and is responsible for shortening the vocal folds.
| Characteristics | Values |
|---|---|
| Muscle Name | Vocalis muscle |
| Muscle Group | Intrinsic |
| Attachments | Originates from the vocal process of the arytenoid cartilage and attaches to the vocal ligament |
| Function | Shortens the vocal folds, tenses the anterior vocal ligament, and relaxes the posterior vocal ligament |
| Innervation | Inferior laryngeal nerve (branch of recurrent laryngeal nerve) |
| Other Functions of Intrinsic Muscles | Control the shape of the rima glottidis (opening between the vocal folds and the arytenoid cartilages), and the length and tension of the vocal folds |
Explore related products
What You'll Learn
The thyroarytenoid muscle shortens vocal folds
The thyroarytenoid muscle is a broad, thin muscle that forms the body of the vocal fold. It supports the wall of the ventricle and its appendix. It originates from the angle of the thyroid cartilage and the adjacent cricothyroid ligament. Its fibres pass backward and laterally, inserting into the base and anterior surface of the arytenoid cartilage.
The thyroarytenoid muscle shortens the vocal folds. It does this by pulling the arytenoid (back) end of the vocal folds toward the thyroid (front) end. This action also serves to bunch up the vocal folds, causing them to vibrate more slowly, resulting in a lower pitch. The thyroarytenoid muscle also helps to strengthen glottic closure, which involves bringing the vocal folds together and keeping them together to resist the airstream from the lungs.
The thyroarytenoid muscle is an intrinsic laryngeal muscle. It is innervated by the recurrent laryngeal nerve, a branch of the vagus nerve. It also receives a communicating branch from the external laryngeal nerve. The muscle is supplied by the laryngeal branches of the superior and inferior thyroid arteries and is drained by the internal jugular vein, via the superior and inferior laryngeal veins.
The thyroarytenoid muscle is made up of two parts with different attachments and directions, which makes its action rather complicated. The deeper portion is connected to the vocal fold and is believed to modify its elasticity and tension. The lateral portion rotates the arytenoid cartilage inward, narrowing the rima glottidis by bringing the two vocal folds together.
Muscle-Bound Fish: Unveiling an Unlikely Consumer Relationship
You may want to see also
Explore related products
Vocalis muscle shortens vocal folds
The vocalis muscle shortens the vocal folds. The vocal folds, also known as the vocal cords, are one of the most important parts of the larynx, playing a key role in breathing, swallowing, and vocalization. The larynx itself is a flexible structure with a cartilaginous core, interconnecting membranes, and associated musculature. The vocalis muscle runs alongside the vocal ligament within the vocal folds. The vocal ligament and the absence of blood vessels on the fold surfaces contribute to their characteristic white appearance, contrasting with the pink hue of the vestibular folds.
The vocal folds are made of muscles covered by a thin layer called mucosa. There is a right and left fold, forming a "V" when viewed from above. The vocalis muscle runs along the lateral aspect of the vocal ligament, shortening the vocal folds. The intrinsic laryngeal 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) and the length and tension of the vocal folds. The rima glottidis is narrowed by the lateral cricoarytenoid muscles, which modulate the tone and volume of speech.
The vocalis muscle is one of the intrinsic muscles of the larynx. All the intrinsic muscles of the larynx (except the cricothyroid) are innervated by the inferior laryngeal nerve, which is the terminal branch of the recurrent laryngeal nerve, itself a branch of the vagus nerve. The cricothyroid muscle, also known as the "singer's muscle", stretches and tenses the vocal ligaments, playing a role in creating forceful speech and altering tone. The recurrent laryngeal nerve is responsible for innervating all muscles of the larynx except the cricothyroid muscle.
The extrinsic muscles of the larynx, on the other hand, contribute to the gross movement of the larynx. They are found in bilateral pairs and their innervation varies, involving the ansa cervicalis, trigeminal nerve, facial nerve, glossopharyngeal nerve, and hypoglossal nerve. The extrinsic muscles do not affect the movement of the vocal folds, but they do raise and lower the entire larynx, which is important for swallowing. The supra- and infrahyoid muscle groups attach to the hyoid bone, allowing the whole of the larynx to be moved as one unit.
Caffeine's Effect on the Heart: Cardiac Muscle and More
You may want to see also
Explore related products
Cricothyroid muscle raises pitch
The cricothyroid muscle, often referred to as the "singer's muscle", is a muscle in the larynx that plays a crucial role in controlling the tension and length of the vocal cords, thereby influencing vocal pitch.
The cricothyroid muscle is innervated by the external branch of the superior laryngeal nerve, which is a component of the vagus nerve system. It originates from the anterolateral aspect of the cricoid cartilage and attaches to the inferior margin and inferior horn of the thyroid cartilage. When the cricothyroid muscle contracts, it pulls the cricoid cartilage towards the thyroid cartilage, increasing the distance between the anterior (thyroid) and posterior (arytenoid) fixation points of the vocal folds. This action stretches the vocal folds, increasing their tension and length.
The tension and length of the vocal folds are critical factors in determining vocal pitch. As the cricothyroid muscle contracts and stretches the vocal folds, it raises the fundamental frequency (F0) of vibration, resulting in a higher pitch of the voice. This increase in pitch is particularly important for singers, as it allows for a wider range of melodic expression.
In addition to its role in pitch modulation, the cricothyroid muscle also contributes to the creation of forceful speech. By increasing the tension and stiffness of the vocal folds, it enables the production of louder and more resonant sounds. This function is especially relevant in situations where clear and powerful communication is necessary, such as public speaking or vocal performances.
It is important to note that the cricothyroid muscle does not work in isolation. It collaborates with other intrinsic laryngeal muscles, particularly the thyroarytenoid muscle, to fine-tune vocal pitch and produce a range of vocal expressions. The interaction between these muscles and their respective contractions can result in either a decrease or an increase in vocal pitch, depending on the specific frequencies and amplitudes of vocalization.
Firm Muscles: A Myth or Reality?
You may want to see also
Explore related products
Posterior cricoarytenoid muscle abducts vocal folds
The posterior cricoarytenoid muscle is the only muscle that abducts the vocal folds. It originates from the posterior surface of the cricoid cartilage and attaches to the muscular process of the arytenoid cartilage. The contraction of this muscle rotates the arytenoid cartilages laterally and pulls them posterolaterally, separating the vocal cords and assisting the other intrinsic muscles in lengthening the vocal cords. This allows for the passage of air during inspiration and expiration, making the posterior cricoarytenoid muscle essential for respiration.
The posterior cricoarytenoid muscle is a crucial component of the laryngeal musculature and plays a vital role in vocal function and respiration. It is one of the intrinsic muscles of the larynx and is instrumental in modulating vocal pitch and controlling airflow, making it essential for various aspects of speech and respiratory physiology. The superior and inferior thyroid arteries' laryngeal branches supply this muscle.
The posterior cricoarytenoid muscle is also involved in the production of unvoiced sounds, such as letters that do not require a vibration of the vocal cords. Its failure is usually due to damage to the recurrent laryngeal nerve, which can occur during thyroidectomy operations or due to diseases of surrounding organs that compress or infiltrate the nerve. Bilateral palsy of this nerve can cause paralysis of the posterior cricoarytenoid muscle, leading to a potentially life-threatening condition due to possible asphyxia.
As the only muscle that can open the glottis, paralysis of the posterior cricoarytenoid muscle can have severe consequences. It can result in hypoxia and even lead to death. However, the role of this muscle in phonation is not yet fully understood. While it is known to be involved in the production of unvoiced sounds, its specific function in vocalisation remains unclear.
What Causes Muscles to Quiver and How to Stop It
You may want to see also
Explore related products
Lateral cricoarytenoid muscle adducts vocal folds
The lateral cricoarytenoid muscle is one of the intrinsic laryngeal muscles, which are involved in the production of sound through phonation. The intrinsic laryngeal 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) and the length and tension of the vocal folds.
The lateral cricoarytenoid muscle is one of the major adductors of the vocal folds. Adduction of the vocal folds involves the medial swinging of the vocal process, which causes the vocal ligaments to come together, resulting in the closure of the anterior part of the rima glottidis. This process is essential for sound production. The lateral cricoarytenoid muscle also modulates the tone and volume of speech.
The lateral cricoarytenoid muscle originates from the arch of the cricoid cartilage and attaches to the muscular process of the arytenoid cartilage. When the lateral cricoarytenoid muscle contracts, it rotates the arytenoid cartilages, bringing the tips of the vocal processes together and resulting in adduction of the vocal folds. This muscle is also involved in controlling the degree of glottis closure by rotating the arytenoid cartilages towards the midline.
The lateral cricoarytenoid muscle works in conjunction with other muscles to produce sound. For example, it interacts with the thyroarytenoid muscle, which makes up the body of the vocal folds and provides stiffness to the vocal folds through isometric contraction. Additionally, the transverse and oblique arytenoid muscles work simultaneously with the lateral cricoarytenoid muscle to pull the arytenoid cartilages toward each other, closing the posterior part of the rima glottidis.
Alcohol and Muscle Gain: Friends or Foes?
You may want to see also
Frequently asked questions
The vocal folds, also known as the vocal cords, are a key part of the larynx. They play a role in breathing, swallowing and vocalization.
The intrinsic muscles of the larynx 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 vocalis muscle shortens the vocal folds. It runs alongside the vocal ligament within the folds.
The cricothyroid muscle stretches and tenses the vocal ligaments, altering the tone of voice. It is also known as the 'singer's muscle'.
Vocal fold paralysis occurs when one or two of the recurrent laryngeal nerves are injured. This results in hoarseness due to reduced movement of the vocal folds.
