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Name: Ashley
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Dear Newton,
Why do we have dreams?

The measurement of brain waves have shown through research that sleep is not all the same. A night sleep seems to have a series of regular cycles. One of these stages is called "Dream Sleep" or "Rapid Eye Movement" sleep because your eyes move rapidly behind your eyelids during this phase. It is thus labeled REM sleep. REM sleep is not really light sleep or deep sleep, but is characterized by faster breathing and heart rate than other stages of sleep. The brain has increased blood flow and uses more oxygen during REM sleep. This may explain why people awaken during REM sleep often have vivid memories of dreams. The first REM period occurs about 1-2 hours after falling asleep and is the longest of the 4-5 REM periods in a normal night's sleep. They occur once every 90 minutes or so.

The key aspect to address your question is that the brain is very active during REM sleep and may explain the dream phenomenon.

Further information can be obtained through an encyclopedia.

Steven D Sample

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