Frequent waking throughout the night may impair your ability to remember new things, according to a new Stanford University study on mice, published in the Proceedings of the National Academy of Sciences.
Past studies have shown that people with certain neurological and psychiatric conditions, such as alcoholism and sleep apnea, often have memory issues, and new moms have also been found to have "momnesia." But researchers have not been able to pinpoint whether it was the quality of their sleep, their total amount of sleep or the interruptions that affected memory. This study finds that the frequent wakings are what hurts the memory--even if the total number of hours slept is the same.
The Sleep Study
Researchers at Stanford University used mice to test how sleep interruptions affected their memory. Through a process called optogenetics, they activated certain neurons, which play a key role in arousal, at intervals throughout their sleep cycles in order to fragment sleep without affecting its overall amount or intensity.
They found the mice with fragmented sleep couldn't remember what they had learned the previous day. The results, explained H. Craig Heller, Ph.D, on of the study's authors, "point to a specific characteristic of sleep--continuity--as being critical for memory." The study fell short of concluding the amount of uninterrupted sleep needed to avoid memory impairment in humans, but people with sleep apnea, nursing mothers, and those with other sleep disorders are at increased risk.
Some things to do if your sleep is interrupted:
- Look at the cause of the interruptions. For instance, are your children sleeping in bed with you because of frequent nightmares or separation issues? Consider setting up a "bed" next to yours. Is your spouse snoring loudly? Try ear plugs.
- If you're a new parent and have an important meeting or event for which you need to be at the top of your game, ask your spouse to handle the night feedings so you can get a good night's rest.
- Can't figure out the source? Get tested and treated for sleep apnea, which causes you to wake up hundreds of times each night.