Taking a nap appears to improve preschool children's spatial learning and recall, researchers said last week.
"The results of this study provide direct evidence for a benefit of napping on spatial memory in preschool-aged children, regardless of age," they wrote in a presentation given at the annual meeting of the Associated Professional Sleep Societies in Boston, Massachusetts.
What's more, while a nap protects kids' ability to learn, "about a 10% loss of memory is seen when they don't nap," said Dr Rebecca Spencer, a sleep psychologist at the University of Massachusetts, Amherst.
Brain is very active
"This shows that the naps aren't just an 'off-line' period - the brain is very active, essentially still learning. So the nap serves an academic benefit," said Dr Spencer, the senior investigator on the study.
The researchers taught 43 children with a mean age of four years to locate images on a grid, with varying degrees of difficulty depending on each child's age. Then the children took naps. When they woke, they demonstrated how much of the lesson they remembered. Researchers compared the result to a similar test of the same children in which the children were awake for the duration of their nap time.
After sleeping, the children performed better compared to when they stayed awake (p=0.035).
Sleep important for memory
The researchers adjusted for possible confounders including the child's age and nap duration, but the results persisted.
Another expert who attended the meeting, Dr Matthew Tucker, a sleep and memory specialist at Harvard Medical School, told Reuters Health, "I saw the oral presentation for this poster. The research is impressive and timely, especially in light of the recent push in some school districts to eliminate napping programmes at the preschool level."
The results, he added, "leave little doubt that sleep is important for memory processing during this critical stage of development."
(Rob Goodier, Reuters Health, June 2012)
Brain, memory and cognition