Non-REM dreams refer to dreams that are more likely to consist of brief, fragmentary impressions that are less emotional and less likely to involve visual images than REM sleep dreams
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REM Dreams and Non-REM dreams are very different from each other in a few major ways. The first difference between the two is Non-REM dreams consist of brief, fragmentary impressions. They are also less likely to involve visual images compared to REM sleep, and are more frequently forgotten. Non-REM dreams are like thinking about something during the day for a brief period of time while REM dreams are comparable to thinking deeply about something. REM sleep consists of about two hours a night while Non-REM sleep lasts about four to six hours.