Sleep during the whole night.

Sleep stage scoring for both NonREM sleep and REM sleep experiments is based on 30-s epochs and mean ± SEM time in the different sleep stages is given as percentage of total sleep time (TST). SO, Sleep onset; SWS, Slow wave sleep. Latency (in min) of sleep onset is calculated with reference to lights off (23.00 h); latencies to SWS and REM sleep are calculated with reference to sleep onset.*P