Studies have shown that sleep affects markedly on our ability to remember things. Sleep is very essential to build and retain memory. Studies and experiments have been performed on both humans and animals.

Experiments were done on rats which showed that sleep restricted rats did not remember the paths well than those who were not sleep restricted. It is especially helpful for declarative memory than non-declarative. Declarative memory deals with remembering facts and events.

“The cerebellum, which functions as one of the brain’s motor centers controlling speed and accuracy was clearly more active when the subjects had had a night of sleep,” explains Matthew Walker, an Assistant Professor of Psychiatry at Harvard Medical School.

During REM sleep, some chemical messengers like the acetylcholine which is an excellent memory booster go up.
The MRI results showed more activity in certain areas of the brain when the person was asleep. But, the brain’s limbic system, a region that controls emotions like stress and anxiety, showed reduced activity.

When one sleeps, one’s memory shifts to more efficient storage regions of the brain. MRI scans show a dramatic shift in the brain regions while asleep. One consolidates all that one had learnt during the day while one is asleep. Sleep is considered to be very essential in the rehabilitation of those recovering from stroke and brain injuries.