ultradian rhythms

Question 1

ultradian rhythms

Answer 1

biological rhythm with FRQUENCY of more than one cycle in 24 hours

Question 2

sleep cycle

Answer 2

approx. 90 mins
monitored by EEG

1/ stages 1+2= light sleep (alpha to theta waves)
2/ stages 3+4= deep sleep (delta waves)
3/ stage 5= REM