For Better Memory, Sleep On It

Researchers find that a good night’s rest enhances learning and recall.
To boost your learning and sharpen your memory, skip the brain teasers and string around your finger. Take a nap. You won’t merely be resting—your brain continues to learn while you’re asleep.
Researchers at Michigan State University completed a study suggesting that the ability to learn while asleep is a distinct form of memory, separate from other forms. The study also suggests that individual differences in “sleep memory” affect performance while awake.

Whether you’re trying to master a difficult piano or guitar piece, parsing irregular verbs, or organizing facts and figures for a presentation, you stand a better chance of doing well tomorrow if you get a solid night’s sleep tonight.
“When we sleep, we’re reinforcing learned memories, experiences and behaviors that occurred during the daytime,” said Dr. Wesley Fleming, medical director of Sleep Center Orange County.
In the Michigan State study, researchers showed 48 pairs of related words, such as forest/timber and blacksmith/metal, to 255 participants. In the “awake” group, participants studied the pairs of words at 9 a.m., and completed a recall test immediately afterward in which they were shown one word and asked to remember the second word in all 48 pairs. They took a second test on the words at 7 p.m., along with another test involving equations and letters.
In the “sleep” group, participants studied the word pairs and took the first test at 7 p.m., then were tested again at 9 the following morning, after a night’s sleep. They did significantly better on the second test than the awake group, reinforcing the idea that the brain continues to process information on an unconscious level during sleep.
In findings published in the Journal of Experimental Psychology, the researchers also speculate that people with a greater ability to process and recall information while awake have an increased capacity for unconscious, or sleep memory. Study participants who recalled more word pairs immediately after they studied them also had higher scores, and increased recall, after they had slept. So, if you have a good memory to begin with, you might derive even more benefit from sleep.
A National Sleep Foundation survey reported that 43 percent of Americans say they rarely or never get a good night’s sleep during the week. Anyone who has felt befuddled during a test after an all-nighter or befogged during an early morning meeting knows that insufficient or poor quality rest affects performance.
Both the quality and quantity of sleep count, said Dr. Fleming. Even a long stretch in bed won’t do you much good if your sleep is fragmented by alcohol before bed, sleep apnea, low oxygen, restless legs or snoring (yours or a bedmate’s).