Figure 4

Panel A depicts R-R interval durations for an animal in the CON group over four baseline days (BLD1–BLD4). Panel B shows HRV spectra (bin width = 0.005 Hz) corresponding to full records (150 s long) of time series in Panel A. Panel C contains horizontal Box and Whisker plots of R-R interval durations for different segments of the ventilatory cycle: I, inspiration; IE, inspiratory to expiratory transition; E, expiration; EI, expiratory to inspiratory transition. The vertical line in each box represents the median value of R-R interval duration for each segment, the left and right boundaries of each box indicate the 25^th and 75^th percentile values, and left and right whiskers (resembling error bars) mark the 5^th and 95^th percentile values. Asterisks indicated that R-R interval durations occurring in either E or EI segments were significantly longer than those of either I or IE segments. The finding that R-R interval durations of EI segments were significantly longer than those of E segments is signified by the pound sign (#). Panel D shows a representative breath, inspiration down, with superimposed vertical lines indicating the temporal locations of R waves with reference to ventilatory segments: E, EI, I, and IE. The elapsed time between contiguous R waves, i.e., R-R interval durations, is given in seconds.