Figure 2.

Peak inspiratory (Peak) and expiratory tonic (Tonic) activity of the genioglossus (GG), tensor palatini (TP), end-expiratory lung volume (EELV), inspired minute ventilation (V_I) and epiglottic pressure (P_EPI) on the breath before (Prior) respiratory events, first (+1 to +3) and last (−3 to −1) 3 respiratory efforts during events and breath following (Post) respiratory events in stage 2 sleep and corresponding time periods (8 breath averages) of stable stage 2 sleep. Muscle activity is expressed as a percent of the average activity across both states in each subject (% total activity) due to high variability in the absolute level of muscle activity between subjects (range 3.9 to 38.2 % max). Mean (SEM) presented, n = 10. *indicates P < 0.05 between cyclical and stable conditions on these breaths/efforts by post hoc testing.