Figure 3.

Percent and number (n) of arousals that occur during inspiration and expiration (A) and their distribution with respect to breath timing (B). Mean nadir epiglottic pressure (Pepi) calculated from the inspiratory effort just prior to the arousal breath (C), and nadir Pepi occurrence with respect to breath timing (D). Error bars represent the 95% confidence intervals. Horizontal line (green) indicates the % expected by chance (9.09%) and * indicates a significant difference in arousal probability from chance (B). See Supplementary Material for breakdown of bin and error bar values (including standard error and standard deviation for epiglottic pressure; Supplementary Table S1). Of a total of 354 arousals, 65% occurred during inspiration and 35% occurred during expiration (A). Inspiratory arousals had a uniform distribution throughout inspiration (B) and no temporal relationship with nadir epiglottic pressure, which occurred in the latter stages of inspiration (D). Expiratory arousals occurred predominantly in early expiration (B).