There are two main categories of sleep, Non-Rapid Eye Movement or Non-REM (NREM) and Rapid Eye Movement (REM). NREM sleep contains all stages of sleep except REM (there are 5, although many debate this, instead saying there are 4 stages of sleep).

Non-REM sleep contains light stages of sleep (stage 1), to full sleep (Stage 2), and deep or slow wave sleep (stages 3 and 4).

Alleydog Psychology Trivia Question - Are You Game?


Question: _______________ theory suggests that extroverts end up making choices that place themselves in more positive situations.


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