Study shows sleep helps improve memory

BOSTON (AP) _ Forget about pulling an all-nighter before an exam _ a new study suggests it's more important to get a good night's rest. <br><br>Harvard Medical School researchers, led by assistant

Tuesday, November 21st 2000, 12:00 am

By: News On 6

BOSTON (AP) _ Forget about pulling an all-nighter before an exam _ a new study suggests it's more important to get a good night's rest.

Harvard Medical School researchers, led by assistant professor of psychiatry Robert Stickgold, found that people who slept after learning and practicing a new task remembered more about it the next day when compared to people who stay up all night after learning the same thing.

The study, which will be published in the December issue of Nature Neuroscience, was released Tuesday.

``You need sleep that first night if you want to improve on a task,'' Stickgold said.

The study is another piece in a growing body of evidence that suggests proper rest is necessary for learning, he said.

The 24 test subjects in the study were trained to identify the orientation of three diagonal bars flashed for one-sixtieth of a second on a horizontal-striped computer screen.

Half of the participants went to sleep that night. The other half was kept awake until the second night of the study. Both groups were allowed to sleep on the second and third nights.

On the fourth day, both groups were tested on how proficient they had become at identifying the orientation of the diagonal bars. Those who slept on the first night performed better than they had the first day. Those who didn't sleep did not improve

``We think getting that first night's sleep starts the process of memory consolidation,'' Stickgold said. ``It seems that memories normally wash out of the brain unless some process nails them down.''

Joseph Modrack, an assistant professor of sleep medicine at the University of Rochester, agreed with the findings.

``We don't know a lot about sleep, but we do know that it's useful in terms of deciding what information is useful and what's superfluous and can be discarded,'' he said. ``This study makes a lot of sense.''

Modrack said the people who can benefit most from the study are parents, who can adjust their children's sleep schedule.

``A lot of children just don't get enough sleep,'' he said. ``That's something that could be having a big impact in terms of grades.''

In a previous study, Stickgold and his colleagues found that people who learned a new task did not improve when tested later the same day, but did improve after a night of sleep.

With these studies complete, Stickgold said the researchers are now planning to look into another form of sleep: the 10-minute power nap.

``We're getting set now,'' he said. ``We want to ask the question to see if power napping enhances performance or not.''