Gentle sound stimulation played during specific times during deep sleep enhanced deep or slow-wave sleep for people with mild cognitive impairment, who are at risk for Alzheimer’s disease.
The individuals whose brains responded the most robustly to the sound stimulation showed an improved memory response the following day.
“Our findings suggest slow-wave or deep sleep is a viable and potentially important therapeutic target in people with mild cognitive impairment,” said Dr. Roneil Malkani, assistant professor of neurology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine sleep medicine physician. “The results deepen our understanding of the importance of sleep in memory, even when there is memory loss.”
Deep sleep is critical for memory consolidation. Several sleep disturbances have been observed in people with mild cognitive impairment. The most pronounced changes include reduced amount of time spent in the deepest stage of sleep.
“There is a great need to identify new targets for treatment of mild cognitive impairment and Alzheimer’s disease,” Malkani added. Northwestern scientists had previously shown that sound stimulation improved memory in older adults in a 2017 study.