SLEEP HELPS WHEN IT COMES TO RECALLING MEMORIES

THE 2-MINUTE READ

A NEW STUDY by researchers at the University of York and Harvard Medical School suggests that sleep not only helps in learning a new piece of information, such as a new phone number or a new word, but also gets the brain to file it away so it is available when needed.
    The scientists found that sleep helps people to remember a newly learned word and incorporate new vocabulary into their "mental lexicon".
    During the study, researchers taught volunteers new words in the evening, followed by an immediate test. The volunteers slept overnight in the laboratory while their brain activity was recorded using an electroencephalogram, or EEG.
    A test the following morning revealed that they could remember more words than they did immediately after learning them, and they could recognise them faster demonstrating that sleep had strengthened the new memories.
    This did not occur in a control group of volunteers who were trained in the morning and re-tested in the evening, with no sleep in between.
    An examination of the sleep volunteers' brainwaves showed that deep sleep (slow-wave sleep) rather than rapid eye movement (REM) sleep or light sleep helped in strengthening the new memories.
    When the researchers examined whether the new words had been integrated with existing knowledge in the mental lexicon, they discovered the involvement of a different type of activity in the sleeping brain.
    Sleep spindles are brief but intense bursts of brain activity that reflect information transfer between different memory stores in the brain — the hippocampus deep in the brain and the neocortex, the surface of the brain.
    — ANI