Sleep fuels new memories

A lack of sleep disrupts the functioning of the hippocampus - the area of the brain involved in forming new memories - and this could explain why children who don't get enough sleep tend to do poorly in school, say Harvard Medical School researchers.

Their study included 28 volunteers who were randomly deprived of sleep for two days and a night or who were allowed to sleep normally. After that time, the volunteers were given a test that involved looking at and remembering a series of pictures, Agence France Presse reported.

While they did the test, the volunteers' cerebral activity was monitored using functional magnetic resonance imaging (fMRI). The sleep-deprived participants did slightly worse on the test than those who got their normal amount of sleep.

Lower hippocampus activity
The fMRI revealed that the sleep-deprived volunteers had far lower levels of hippocampus activity during the test than the sleepers, and this affected other areas of the brain linked to alertness, AFP reported.

The findings were published Sunday in the journal Nature Neuroscience.

"These results demonstrate that an absence of prior sleep substantially compromises the neural and behavioural capacity for committing new experiences to memory," the study authors wrote. "It therefore appears that sleep before learning is critical in preparing the human brain for next-day memory formation - a worrying finding considering society's increasing erosion of sleep time." – (HealthDayNews)

Read more:
Sleep Centre
Lack of sleep harms memory

February 2007