What is the major motor nerve for the intrinsic muscles of the larynx?

The major motor nerve responsible for innervating the intrinsic muscles of the larynx is the recurrent laryngeal nerve. This nerve is a branch of the vagus nerve, and it plays a critical role in controlling the movements of the vocal cords, which are essential for phonation (the production of sound) and airway protection.

The recurrent laryngeal nerve innervates almost all the intrinsic muscles of the larynx, except for the cricothyroid muscle, which is supplied by the superior laryngeal nerve. This distinction highlights the importance of the recurrent laryngeal nerve in the overall function and coordination of the laryngeal muscles, facilitating actions such as adjusting the tension of the vocal folds and opening or closing the airway during breathing.

The vagus nerve, although pivotal in innervating many structures in the neck and thorax, does not serve as the direct motor nerve for these intrinsic muscles. The phrenic nerve primarily innervates the diaphragm, which is crucial for respiration but not directly related to laryngeal function. The superior laryngeal nerve, while it does contribute to laryngeal function by innervating the cricothyroid muscle for pitch modulation,