For this study, the researchers wanted to investigate the relationship between sleep, memory and beta-amyloid deposits, one of the main factors in the development of Alzheimer’s disease. To do this, they studied a small sample of participants who did No suffer from Alzheimer’s disease, half of whom had large amounts of amyloid deposits.

The participants’ brain waves were monitored during sleep in the laboratory using an electroencephalograph (EEG). After waking up, they performed tasks that tested their memory.

Of course, among participants with more amyloid deposits, those who had deeper sleep performed better on memory tasks than those who did not do sleep too

Thus, the researchers believe that these findings indicate that deep sleep is a protective factor against memory decline in those with amyloid deposits, even in those not diagnosed with Alzheimer’s disease.

As senior study author Matthew Walker, Ph.D., explained in a press release, “Think of deep sleep almost as a life raft that keeps the memory afloat, rather than the memory being dragged down by the weight of Alzheimer’s pathology.” He adds that it now appears that deep NREM sleep “may be a new, missing piece in the explanatory puzzle of cognitive reserve.”