It turns out that seven hours of sleep a night may be the ideal amount for keeping your brain in good health if you're middle-aged or older.
"Getting a good night's sleep is important at all stages of life, but particularly as we age.
Finding ways to improve sleep for older people could be crucial to helping them maintain good mental health and well-being and avoiding cognitive decline
the investigators analyzed data on sleep patterns, mental health and well-being from nearly 500,000 British adults, aged 38 to 73, who completed a series of thinking tests.
They were also more likely to have symptoms of anxiety and depression, and worse overall mental well-being.
"While we can't say conclusively that too little or too much sleep causes cognitive problems, our analysis looking at individuals