Vivid dreams 'improve our memories'

And make us better problem solvers:

People who enjoy a dream-filled sleep are significantly better at recalling information and making links between facts when they wake, scientists found.

But recharging with a shallow nap offers no such mental boost, the research suggests.

The results of the study add to the growing body of evidence that Rapid Eye Movement (REM) sleep – the stage of slumber when our most intensely remembered dreams occur – is crucial to the brain’s ability to lay down and consolidate memories.

An average night’s repose includes four or five spells of REM sleep, but these bursts tend to be lengthier towards the end of the night.

This means that adults who get less than the recommended seven to eight hours a night – and therefore insufficient REM sleep – may be damaging their mind’s ability to form strong memories.

Although REM sleep is not classified as a type of deep sleep, it is only reached after the brain has passed through deep sleep stages.
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Dr Sara Mednick, a sleep researcher at the University of California in San Diego who led the study, believes that the formation of connections between previously unassociated information in the brain – which leads to creative problem-solving – is encouraged by neurological changes which occur during REM sleep.

She said: "REM sleep is important for pulling together all the information we process on a daily basis and turning it into memories we can use later.

"This helps us to understand more about the benefits of sleep and to help people maximise their sleep schedules for optimal productivity and memory retrieval."
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They found that people woken while their closed eyes made jerking movements recalled much more colourful and elaborate dreams than people woken during other stages of sleep.

It is now believed that sleep acts as a sort of mental filing system, enabling the brain to sort relevant information that needs to be retained from useless information which can be discarded. This process may take place as memories are shifted from one part of the brain to others.

I know I need my eight hours in order to function properly - and I have very vivid dreams. I think of dreams as similar to a computer's "disk clean-up and defragmenting" functions - but my dreams are very entertaining and usually more vivid than 3D movies.