Figure 8 - Intrathoracic pressure is plotted with respect to time (t) in the spontaneously breathing animal.

Inspiratory and expiratory phases are arbitrarily subdivided into early and late segments. (Source: Ikari T, Sasaki CT. Glottic closure reflex: control mechanisms Ann Otol Rhino Laryngol 1980;89(3): 220-224, with permission from Annals Publishing Co.)