Deep sleep is critical for memory consolidation. But beginning in middle age, deep sleep decreases substantially, which scientists believe contributes to memory loss in aging.

The sound stimulation significantly enhanced deep sleep in participants and their scores on a memory test.

“This is an innovative, simple and safe non-medication approach that may help improve brain health,” said senior author Dr. Phyllis Zee, professor of neurology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine sleep specialist. “This is a potential tool for enhancing memory in older populations and attenuating normal age-related memory decline.”

The study will be published March 8 in Frontiers in Human Neuroscience.