Too much or too little sleep both affect your brain

Those in the study who reported short sleep duration defined in the study as six hours or less had raised levels of beta-amyloid, which "greatly increases" risk for dementia, said the study's lead author Joe Wine.

At a more advanced level, sleep deprivation can over-stimulate parts of the brain and even lead to permanent brain damage, according to a report on sleep deprivation among students published by The Guardian. “This is because of the brain's neural plasticity which means its ability to adapt to new situations.’’

While pulling a late night once in a while isn't great for your health, repeating it could lead to permanent brain damage.

Also, Participants who reported long sleep duration (nine or more hours) scored slightly worse on the Digit Symbol Substitution Test than those who reported normal sleep duration. Sleeping too much can reduce the cognitive ability and reasoning skills, causing a permanent loss of brain cells, research indicates.

The main takeaway is that it is important to maintain an organized schedule to balance your sleeping hours between 6-9 hours; no more, no less.

"Additionally, both people who get too little sleep and people who get too much sleep had higher (body-mass index and) more depressive symptoms." The findings suggested that short and long sleep might involve different underlying disease processes, Winer added. 

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