Sleeping is a vital part of the learning process

Students who stay up all night revising might be doing more harm than good to their exam chances, say researchers in the United States.

Researchers at Harvard Medical School in Boston say that losing out on sleep disrupts students' ability to learn and remember.

The study reports that sleep is an important aspect of the learning process and that if students miss out on sleep their ability to perform academic tasks declines.

And even if students tried to catch up on missed sleep, the negative impact on performance was still apparent three days after the initial loss of sleep.

This would mean that even if students were sleeping the night before an exam, their performance could be adversely affected by an all-night revision session from a few days before.

Sleep deprivation

Researchers measured the way that a group of students were able to learn sequences of patterns over four days - with some of the group being deprived of sleep on the first night and others enjoying a full night's sleep.

And the researchers concluded that there was a link between lack of sleep on the first night and a subsequent under-performance in memory tests several days later.

The suggestion is that sleep plays an important part in the way that people learn, with the sleep process helping to make new information "stick".

"Our research shows that you need sleep that first night if you want to improve on a task," said Robert Stickgold, a psychiatrist at Harvard Medical School.

"We think that getting that first night's sleep starts the process of memory consolidation. It seems that memories normally wash out of the brain unless some process nails them down. My suspicion is that sleep is one of those things that does the nailing down," he said.

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