Regarding REM and NREM sleep, which of the following statements is TRUE?
A) Daytime stress can increase NREM sleep.
B) Physical exertion can increase REM sleep.
C) NREM sleep is deepest early in the night during the first few stage 4 periods.
D) Mammals, such as dogs and cats, do not show REM sleep.

Question

Quizplus · Accepted Answer

NREM sleep is deepest early in the night during the first few stage 4 periods. This is when the body is in the deepest level of sleep and often experiences sleepwalking, bedwetting or night terrors. As the night progresses, the body spends less time in deep sleep and more time in REM sleep.

Option A is incorrect because stress leads to less NREM sleep and more REM sleep. 
Option B is incorrect because physical exertion does not necessarily increase REM sleep, but it can increase the total amount of deep sleep. 
Option D is incorrect because mammals, including dogs and cats, have been observed to have REM sleep.

Regarding REM and NREM Sleep, Which of the Following Statements