Doctors have warned for years that Americans are not getting enough sleep, with health consequences ranging from drowsy driving and irritability to an increased risk of dementia, heart disease and early death. Now, a recent study suggests that one particular type of sleep may be especially important when it comes to how the brain responds to stressful situations.
The research, published in the Journal of Neuroscience, found that people who spent more time in rapid-eye-movement (REM) sleep — the phase when dreaming occurs — had lower fear-related brain activity when they were given mild electric shocks the next day. The findings suggest that getting sufficient REM sleep prior to fearful experiences may make a person less prone to developing post-traumatic stress disorder (PTSD), the authors hypothesize.
The study isn’t the first to suggest that REM sleep delivers unique benefits. Some experts even believe that it’s actually a lack of REM sleep and a lack of dreaming — rather than just poor sleep in general — that’s responsible for many of the health problems Americans suffer from today. Here’s what scientists know so far — and what they suspect — about REM sleep, dreams and what happens when people are deprived of both.