Rem rebound involves the
- tendency for rem sleep to increase following rem sleep deprivation.
- increase in rem sleep that characteristically follows intense learning episodes or stressful daytime experiences.
- unusual symptoms of tiredness and irritability that follow periods of rem sleep deprivation.
- tendency for rem sleep periods to become increasingly longer and more frequent as a normal night of sleep progresses.

The correct answer to the question: REM rebound involves the:___, would be: Tendency for REM sleep to increase following REM sleep deprivation.

Explanation:

REM sleep, also known as Rapid Eye Movement is one of the stages of sleep in which, depending on the depth of sleep, there is a loss of coordination of the muscle movement of the eyes. Usually, this stage of sleep requires a certain amount of time to happen, since it is a deep state, but in REM rebound  what we have is a person who has been deprived of REM sleep for a period of time, and who, after finally falling asleep will experience lenghtier and much more frequent episodes of REM sleep than those who haven´t. As the term "rebound" involves, it is like the body comes back from its forced lack of proper rest and as retribution prolongues these periods to accomplish the needed rest.

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