showed a trendP =0.095
When the δ power in NREMS of the first time point of Rec sleep after SD was expressed as a percentage of the δ power during the time point preceding the SD, the Per3 5/5 mice showed a trend for higher levels of δ power than the Per3 4/4 mice (198.15±14.1 vs. 168.46±9.01%; PROC TTEST, P =0.095).