Respiratory changes associated with rapid eye movements in normo- and hypercapnia during sleep

Department of Applied Physiology, Ruhr-University Bochum, D-44780 Bochum, Germany Rapid eye movements during rapid-eye-movement (REM) sleep are associated with rapid, shallow breathing. We wanted to know whether this effect persisted during increased respiratory drive by CO 2 . In eight healthy subjects, we recorded electroencephalographic, electrooculographic, and electromyographic signals, ventilation, and end-tidal P CO 2 during the night. Inspiratory P CO 2 was changed to increase end-tidal P CO 2 by 3 and 6 Torr. During normocapnia, rapid eye movements were associated with a decrease in total breath time by 0.71 ± 0.19 (SE) s ( P