MOSCOW, 8 Nov – Sleeping longer than 6.5 hours per night may contribute to cognitive decline. This is reported in the scientific journal Brain.
Scientists from the George Washington University School of Medicine conducted a study in which one hundred elderly people, ages 75 to 80, took part. Specialists monitored their condition for five years.
At the start of the experiment, 88 people did not have any signs of dementia, while the remaining 12 participants showed cognitive impairment of varying severity.
Sleep duration and quality were measured at intervals of 4-6 nights using electroencephalography, during which the subjects slept with a special electrode on their forehead.
In addition, the experts took into account factors such as age, heredity, and the presence of deposits of tau protein and beta-amyloid associated with Alzheimer’s disease.
As a result, they were able to find out that low-quality sleep lasting both less than 4.5 hours and more than 6.5 hours has a negative effect on human cognitive functions.
Scientists have repeatedly studied the negative effects of sleep deprivation on mental capacity, but the reasons for the harmful effects of an excess of sleep are still not fully understood.