Figure 4.

The hippocampus and neocortex demonstrate independent simultaneous sleep states. (A) Proportion (mean ± standard error of the mean) of epochs where the hippocampus and neocortex were scored as having the same (Similar) or different (Dissimilar) sleep states when either site was in rapid eye movement (REM) or transition-to-REM sleep (TR) (n = 5 rats). The groups were not significantly different (Student's t-test; two-tailed; P = 0.82). (B) Proportion (Mean ± standard error of the mean) of states scored as TR or REM from hippocampal and neocortical sites at simultaneous epochs resulted in five distinct state-pair categories. State-pair categories follow the notation “hippocampal state/neocortical state” (n = 5 rats). SWS = slow wave sleep.