Deep sleep may provide protection against memory loss in adults who have significant brain changes related to Alzheimer’s disease, a new study has found.
Sleep is known to influence health trajectories. And disrupted sleep has been tied to faster accumulation of beta-amyloid protein in the brain, a hallmark sign of Alzheimer’s that is linked to memory loss. In the new study, investigators sought to find how deep (non-REM, slow-wave) sleep might affect scores on memory tests among healthy older adults who already had a high burden of beta amyloid, based on brain scans.
Sixty-two older healthy adult participants were recruited from the Berkeley Aging Cohort Study. Half had high amounts of amyloid deposits and the other half did not. Their sleep was monitored in a laboratory setting using electroencephalography (EEG).
Better memory performance
After waking, the participants were scored on their responses to a memory task. Those with high beta-amyloid burden who also experienced higher levels of deep sleep outscored their peers who had the same amount of deposits but who slept worse.
This deep sleep effect was not seen in the group without brain pathology. With their cognitive function already intact, there was no demand for additional resilience, the researchers theorized.
Deep sleep may help build cognitive reserve, increasing resilience against the effects of beta-amyloid brain changes, Zsófia Zavecz, PhD, of the University of California Berkeley’s Center for Human Sleep Science said.
The study results are actionable for the population aged 65 years and older, Zavecz added.
“With a certain level of brain pathology, you’re not destined for cognitive symptoms or memory issues. … [T]here are certain lifestyle factors that will help moderate and decrease the effects,” she said. “One of those factors is sleep and specifically, deep sleep.”
Sleeping better and practicing good sleep hygiene can help seniors “gain the benefit of this compensatory function against this type of Alzheimer’s pathology,” she concluded.
Full findings were published in BMC Medicine.