ABSTRACT
The principal event in the development of obstructive sleep apnea is a collapse or near-collapse of the pharyngeal airway during sleep. As a result, understanding the mechanisms that control upper airway patency while awake and how such mechanisms are impacted by sleep is essential if one is to grasp the pathophysiology of this disorder. Therefore, all such mechanisms will be discussed briefly in the beginning of this chapter with a particular focus on the control of the pharyngeal musculature. Thereafter, reflex mechanisms involved in the control of these muscles and how such reflexes are affected by sleep will be addressed at length.
