Figure 6-15 Decrease in phasic inspiratory muscle activity, expressed as the peak height of moving time average (MTA), in percent change from control (1% halothane), during halothane anesthesia in adult cats. Values are expressed as the mean ± SEM. The middle curve represents the intercostal muscle (IC) (*P < .05 compared with the diaphragm [DI]; **P < .05 compared with the genioglossus muscle [GG]). Notice the differential sensitivities of these respiratory muscles. (From Ochiai R, Guthrie RD, Motoyama EK: Effects of varying concentrations of halothane on the activity of the genioglossus, intercostals, and diaphragm in cats: an electromyographic study. Anesthesiology 70:812, 1989.)