Deep sleep is critical to maintaining a robust memory, but both decline with age. A small new study published in Frontiers in Human Neuroscience suggests that one easy way for older adults to get deeper sleep and stronger memories is to listen to a certain soothing sound called “pink noise”
Interestingly, it's generally not the actual noises that bother us, but more so their shift from what we've been used to hearing. Therefore, noises that don't bother you much during the day — the faucet dripping, or your cat cleaning itself, for example — suddenly become your worst nightmare at night.
Pink noise differs from white noise in that it emphasizes lower sound frequencies. The sounds are more natural—think waves on the beach, rain falling, or leaves rustling. You can listen to a sound machine that plays recordings of pink noise, or you can turn on a fan which also emits pink noise.
According to Prevention, pink noise slows down your brain waves and helps regulate them, giving you a steady, long sleep.
It may sound strange, but previous studies have found that playing so-called pink noise during sleep improves the memory of younger adults. “We wanted to see if it would work in older people, too,” says senior author Dr. Phyllis Zee, professor of neurology at Northwestern University Feinberg School of Medicine. Older people tend to get less slow-wave sleep and are at greater risk for memory impairment.
Listening to pink noise can help you fall asleep more quickly since you aren’t kept awake by distracting sounds. It can also improve your sleep quality by prolonging the amount of time you spend in deep sleep, leaving you better rested when you wake up in the morning.
Additionally, sleeping with pink noise may improve your memory. In one study, people who listened to pink noise during sleep performed three times better on subsequent memory tests than they did after nights without the sounds.