Forget white noise. Pink noise can sharpen your mind while you slumber.
By Cassie Shortsleeve
If you use a white noise machine to help you fall asleep at night, it’s time for a change of color.
For older adults, so-called pink noise may be the best way to enhance deep sleep and boost memory, according to research released today out of Northwestern University Feinberg School of Medicine.
For the study, a small group of older adults took a memory test before bed and then dozed off either listening to pink noise or in silence. The next morning, everyone re-took the test. The results? Pink noise listeners performed three times better than they did the night before; those who went to bed in silence only improved by a few percentage points.
“This is an innovative, simple, and safe non-medication approach that may help improve brain health,” Phyllis Zee, M.D., Ph.D., wrote the study’s lead author. “This is a potential tool for enhancing memory in older populations and attenuating normal age-related memory decline.”
Previous research has found that both white and pink noise can help people fall asleep. But pink seems to help people find deeper sleep, which is crucial for making memories, the researchers say. This becomes especially important as you grow older: Starting as early as middle age, our deep sleep decreases, something scientists think can play a role in memory loss as the years go on.
What’s the difference between white and pink? They both cover all the frequencies that the human ear can hear, but the intensity of pink noise decreases as frequency increases. So whereas white noise can sound like static or a hiss, pink noise is smoother and more soothing across all frequencies. Think falling rain, an ocean breeze, a whirling fan—even the muffled sound of your own heartbeat.
In the study, researchers synced up the pink noise itself to the rhythm of people’s brain waves–something you’re not going to do at home. But if you’re hoping to sleep a little sounder (and stay sharp while you’re at it), consider the three apps below. With the tap of a finger, you’ll bring about pink noise—and, hopefully, solid shut-eye.