While we all know how important it is to get a good night’s sleep, new research has shown that sleeping soundly for 8 hours may also help to protect the brain against the memory decline seen in conditions such as Alzheimer’s.
A reduction in deep non-REM sleep may cause a build up of toxic proteins
The study, which was carried out at the University of California-Berkeley, suggests that people who experience reduced deep non-REM sleep, the sleep cycle linked to memory retention, are at a higher risk of developing a build-up of a specific protein in the brain which is believed to trigger Alzheimer’s disease. This build-up of the toxic beta-amyloid protein then leads to further disrupted sleep, which in turn perpetuates the cycle.
A link was established between the amount of sleep and performance in memory tests
Led by Matthew Walker, a neuroscience professor at the university, the study concentrated on 26 older adults with no outward signs of degenerative brain disease. Walker and his colleagues found that poor sleep was associated with higher amounts of the beta-amyloid protein, and that the subjects exhibiting the highest levels of this protein, suffered from poor quality sleep and also showed the worst performance on the memory tests undertaken before and after sleep.
Deep sleep has the ability to remove harmful toxins from our brains
While past research using mice has shown that deep sleep has the ability to clear harmful toxins from the brain, this latest study, which was published in Nature Neuroscience, was carried out using human test subjects and is therefore much more informative. Walker and his team believe that this study will help scientists to develop ways to prevent memory loss by intervening to improve the quality of sleep and thus breaking the causal chain and the build-up of toxic proteins.
Further research will be carried out over the coming five years
The researchers plan to continue their work over the next five years, tracking a new sample of older adults to discover whether it’s the quality of sleep or the protein build up that starts the memory loss cycle.