1 ENTERING SLEEP
3 DEEP SLEEP
4 VERY DEEP SLEEP
A. REM: rapid eye movement desynchronized ecg penile erection
B: Sws slow wave sleep synchronized ecg dreamless
on the rem phase
nucleus: N. suprachiasmaticus
task 1: accepts external visual stimulation by vision(light dark cycle)
task 2: independent biological clock 25(hrs) basal circadian rhythm
A: upper motor system: cortical brain stem
B: Lower motor system: spinal chord segmental
C;segmental spnal movement execution