PREOPTIC-ANTERIOR HYPOTHALAMIC WARMING INCREASES EEG DELTA-FREQUENCY ACTIVITY WITHIN NON-RAPID EYE-MOVEMENT SLEEP

The effects of mild POAH warming and cooling on EEG frequency patterns within sustained periods of NREM sleep were examined. EEG spectral po wer analysis showed that POAH warming increased delta (0.5-4.0 Hz) act ivity, but had no effect on theta or sigma frequencies. Delta power wa s also increased during a 1 h recovery period, following warming. POAH cooling had no EEG effects. Since delta power is thought to be an ind ex of sleep depth, our findings suggest that POAH thermoregulatory mec hanisms participate in the regulation of the depth of NREM sleep.