Deep Sleep Cements Learning

Practice doesn't make perfect — unless it's followed by a good night's sleep.

Yes, practicing a task makes you better at it. But deep sleep after practice makes you better still, suggests a study led by Philippe Peigneux, PhD, of the University of Liege in Belgium.

"Information that is acquired during wakefulness is actively altered, restructured, and strengthened during sleep," Peigneux and colleagues write in the Oct. 28 issue of Neuron.

The Belgian researchers studied a particular kind of learning: spatial memory. It's the kind of memory needed to navigate through a three-dimensional world. Or, as in their study, through the computer game Duke Nukem 3D.

Peigneux's team measured blood flow in the part of the brain called the hippocampus (search), the brain's learning center. They studied three sets of people. One had their brains scanned while navigating through a virtual city in the Duke Nukem game. Another had their brains scanned while sleeping after they had spent time learning their way through the Duke Nukem environment. And a third group had brain scans but didn't play the game.

The brain's learning center got very active while people were learning to navigate through virtual reality. Later, during deep sleep, the same part of the brain became active — but only in those who had played the game.

These findings suggest that learning-dependent changes in brain activity during sleep reflect recent spatial learning, Peigneux and colleagues write.

While deep sleep appears to be important for spatial learning, lighter stages of sleep appear to reinforce other kinds of learning.

So how do you get to Carnegie Hall? The new answer: Practice, practice, and sleep.

By Daniel J. DeNoon, reviewed by Brunilda Nazario, MD

SOURCES: Peigneux, P. Neuron, Oct. 28, 2004; vol 44: pp 535-545. News release, Cell Press.