Heart rate variability during carbachol-induced REM sleep and cataplexy.

•REM sleep (REMc) and cataplexy (CA) were induced by carbachol injections into the NPO.•HRV was evaluated during these conditions and natural sleep and wakefulness.•Heart rate was greater during CA while LF power was larger during natural REM sleep.•In CA there was a decrease in coupling between the tachogram and respiratory activity.•Although the somatomotor atonia was the same, REMc and CA have differences in the HRV.