Drugs, Alcohol, and Sleep

We’ve talked about the effects of sleep deprivation and memory consolidation/learning, but what about a night of drinking? Some students like to unwind on the weekends and have a couple drinks with friends.  However, drinking right before bed suppresses REM sleep while our body works on metabolizing the alcohol.  What does this mean? REM sleep is particularly important for the consolidation of memory and learning. Without REM sleep, the parts of our brain that are in charge of forming new memories get shut down. In particular, our hippocampus becomes temporarily unavailable.  The hippocampus is what creates the new formation of memories so living without a working hippocampus would mean never remembering any facts ever again! Luckily, once our body metabolizes the alcohol we undergo a REM sleep rebound.  Ever woken up really early after a night of drinking?  This is because, once the alcohol is metabolized, we spend most of the time in REM sleep.  REM sleep is the closest state of sleep to the awake state making us extra sensitive from being aroused.  However, the sleep rebound does not bring our brain back to tip-top working shape.  Even up to three days following a night of pre-sleep drinking, our brain continues to have trouble consolidating learned information.  Even so, the sleep we got that night is not “good” sleep so we continue with our sleep deprived state (see the section of sleep deprivation and sleep rebound for more information).  Alcohol isn’t the only drug that suppresses REM sleep.  As a matter of fact, even though people may report falling asleep faster under the influence of marijuana, marijuana also suppresses REM.  Remember: there is more to sleep than your total sleep time- you actually need to be considerate of the quality of sleep you are having per night.