STORRS -- Have you ever slept at a relative’s house or hotel and found that even though you got enough hours of sleep you felt more tired the next morning than usual? In the journal Current Biology last week, scientists at Brown University found that half the brain stays on alert when you are sleeping in unfamiliar surroundings.
When you are asleep you actually transition between light, moderate, and deep sleep. Initially, you are lightly dozing and if that works out you go into deeper sleep for some time and then transition back to lighter sleep and then heavier sleep. You cycle between these various stages of sleep throughout the night.
This study was based off of animal studies in ducks where the ducks sleep in clusters and those ducks on the outside of the cluster that are more likely to be eaten have half of their brain that goes into deep sleep while the other half is more alert. Those ducks on the inside of the cluster slept more soundly with both of their brains resting. The researchers wondered if the same thing happened in humans and used MRIs during sleep to find out. Scientists already knew that being in an unfamiliar place can make it harder to fall asleep than at home or that the lumpy bed can make it harder to stay asleep but what this new study shows is that even when you fall into deeper stages of asleep, only one half of your brain is fully at rest. The left brain is still holding back and is on alert. Like the ducks, this makes it easier for you to wake up if a fox is trying to eat you or your Aunt Beatrice is trying to smother you with a pillow over Thanksgiving but reduces the quality of sleep you receive. They found that introducing a sound that is loud enough to wake up someone lightly sleeping did indeed wake them up if given into the right ear (which is connected to the left brain) but not when introduced in the left ear. The good news is that when you spend the next night in the same place, this effect largely wears off and you are better able to get a good night’s sleep.
Since this is such a new discovery, there are no remedies that have been studied. However, if you are getting poorer quality sleep then trying to get more sleep is valuable. Turning in a bit earlier could help. If you have a big meeting coming up at mid-day, it might be preferable to sleep at home and then drive or fly there the next morning than it would be arrive the night before and sleep over. If you need to stay over, staying over for more than one night to acclimate to the new surroundings can minimize the effect of a poor night’s sleep than that first night. Interestingly, athletes in competitive sports already do this. They don’t come into town, sleep over, and then play a major sporting event the next day. They try to come a few days before to get acclimated.
Dr. Michael White, UConn School of Pharmacy