For this study, researchers wanted to dig into the connection between sleep, memory, and beta-amyloid deposits—one of the primary drivers of Alzheimer’s disease. To do so, they studied a small sample size of participants who did not have Alzheimer’s, half of whom had high amounts of amyloid deposits.
The participants’ brain waves were monitored while they slept in a lab using an electroencephalography (EEG) machine. Upon waking, they completed tasks that tested their memory.
Sure enough, among participants with high amounts of amyloid deposits, those who had more deep sleep performed better on the memory tasks than those who didn’t sleep as well.
As such, the researchers believe these findings point to deep sleep as a protective factor against memory decline in those with amyloid deposits—even in those who have not been diagnosed with Alzheimer’s.
As senior author of the study Matthew Walker, Ph.D., explained in a news release, “Think of deep sleep almost like a life raft that keeps memory afloat rather than memory getting dragged down by the weight of Alzheimer’s disease pathology.” He adds that it now seems that deep NREM sleep “may be a new, missing piece in the explanatory puzzle of cognitive reserve.”
