Which muscle is responsible for the abduction of the vocal folds?

The muscle that is responsible for the abduction of the vocal folds is the posterior cricoarytenoid. This muscle plays a critical role in the movement of the arytenoid cartilages, which, in turn, affects the position of the vocal folds. When the posterior cricoarytenoid contracts, it pulls the arytenoid cartilages apart, resulting in the vocal folds being drawn away from the midline, leading to abduction.

This action is essential for functions such as breathing, as it allows air to pass through the glottis by ensuring the vocal folds are open. Understanding this function is critical, particularly in the context of phonation and airway protection during swallowing, as the status of vocal fold abduction can influence both speech and respiratory functions.