Fig. 4.

Clarity and delay of the local NREM to REM sleep transition of different brain regions. (A) Clarity of the transitions. The clarity of the transition is highest in the posterior cingulate cortex and mesiotemporal regions and lowest in the rest of the temporal lobe. (B) Relative delay of the local transitions in different brain regions. On average, the transitions are observed in the lateral occipital cortex 3 min before the fronto-orbital cortex.