7 Hours of Sleep More Ideal Than 8 to Improve Cognitive Performance and Mental Health, New Study Suggests

A new study found that seven hours is the ideal amount of sleep for individuals in their middle age and upwards, with too little or too much sleep linked to poorer mental health and cognitive performance.

A SciTechDaily report specified that researchers from the University of Cambridge and Fudan University have suggested that sleep is playing a vital role in "enabling cognitive function and maintaining good psychological health.

In addition, sleep is also keeping the brain healthy by eliminating waste products. As a person gets older, he frequently sees alterations in his sleep patterns, which include difficulty falling and staying asleep, as well as decreased sleep quantity and quality.

It is also thought that sleep disruptions may contribute to cognitive decline, not to mention, psychiatric conditions in the aging population.

7 Hours of Sleep, Ideal for Cognitive Performance

In the study, published in the Nature Aging scientific journal, scientists from the United Kingdom and China analyzed data from almost 500,000 adults aged between 38 and 73 years old from the UK Biobank.

Participants were asked about their patterns of sleep, well-being, and mental health. Then, they partook in a series of cognitive tests. Available for nearly 40,000 of the study volunteers were brain imaging and genetic data.

By examining the data, the researchers discovered that both inadequate and excessive duration of sleep were linked to impaired cognitive performance, like processing speed memory, visual attention, and problem-solving skills.

According to the researchers, seven hours of sleep each night was the optimal amount of sleep for cognitive performance, but for good mental health as well, with people suffering from more symptoms of anxiety and depression, and worse general well-being "if they reported sleeping for either shorter or longer duration.

Disruption of 'Slow-Wave,' Deep Sleep

The study investigators said one possible reason for the link between inadequate sleep and decline in cognitive performance may be because of the disruption of "slow-wave, deep sleep."

Essentially, disruption to this sleep type has been shown to have a close association with memory consolidation, as well as the accumulation of amyloid, a key protein which, in terms of misfolds, can result in "tangles" in the brain characteristic of "some forms of dementia," a similar Today UK News said. In addition, lack of sleep is likely to hinder the ability of the brain from ridding itself of toxins.

Furthermore, the research team also discovered an association between the amount of sleep and differences in the brain regions' structure, which are involved in cognitive processing and memory, again, with greater chances linked to greater than, or less than seven hours of sleep.

For Mental Health and General Well-Being

Getting a consistent seven-hour sleep every night, minus too much fluctuation in duration, was essential as well, to cognitive performance, as well as good mental health and well-being.

Previous research also showed that disrupted sleep patterns are linked to increased inflammation, specifying vulnerability to age-related diseases in older people.

China-based Fudan University's Professor Jianfeng said, while it can't be said conclusively that too little or too much sleep is causing cognitive disorders, the researchers' analysis looking at people over a longer period of time appears to back this idea.

Nonetheless, the reasons older people have poorer sleep seem to be complicated, affected by a combination of the genetic makeup and the brain's structure.

Related information about getting enough sleep is shown on Bright Side's YouTube video below:

Check out more news and information on Sleep in Science Times.