At 3 o'clock in the morning,Harry has already slept for four hours.As long as his sleep continues,we can expect an increasing occurrence of
A) hypnagogic sensations.
B) muscle tension.
C) REM sleep.
D) NREM-3 sleep.

Question

Quizplus · Accepted Answer

At around 3-4 hours into a sleep cycle, the body begins to enter into periods of REM (rapid eye movement) sleep, which is characterized by increased brain activity, vivid dreaming and muscle paralysis. Therefore, choice C is the best answer as it predicts an increasing occurrence of REM sleep as Harry continues to sleep. Choices A and B are not likely to increase as sleep continues, and NREM-3 sleep typically occurs earlier in the sleep cycle.

At 3 O'clock in the Morning,Harry Has Already Slept for Four