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Regulated sleep sessions boost brain power dramatically

For those who take power naps, there is plenty of good news coming out of the American Association for the Advancement of Science annual conference in San Diego this week.

Scientists who tested both babies and adults found that the amount and timing of sleep sessions determines how much is learned and remembered.


NGS photo by J. Baylor Roberts

Babies who are able to get in a little daytime nap are more likely to exhibit an advanced level of learning, said scientists from the University of Arizona in Tucson.

A separate study from the University of California, Berkeley, shows that an hour’s nap can dramatically boost and restore adult brain power. National Geographic News published a news story about the UC research on our main news site today. Read: Naps Clear Brain’s Inbox, Improve Learning.


NGS photo by James L. Stanfield

The University of Arizona study found that naps are an integral part of learning for infants, helping the developing brain retain new information, the university said in a news statement.

Don’t wake the baby

“Anyone who grew up in a large family likely remembers hearing ‘Don’t wake the baby.’ While it reinforces the message to older kids to keep it down, research shows that sleep also is an important part of how infants learn more about their new world,” UA said.


NGS stock photo by Jodi Cobb

Rebecca Gomez, Richard Bootzin and Lynn Nadel in the University of Arizona psychology department played recordings of “phrases” created from an artificial language to four dozen 15-month-old infants during a learning session.

Differences arose between the infants who had napped and those who had not.

Prior to being tested, some infants learning this faux language took their normally scheduled naps. Others were scheduled at a time when they would not nap following the session.

When the infants returned to the lab, they again heard the recordings–along with a set of different phrases in which the predictive relationship between the first and last words were new.

“By carefully watching the babies’ facial expressions as they listened to both old and new phrases, the researchers were able to rate their level of attention. They found that babies’ longer gazes at a flashing light that coincided with the phrases signaled attention, which indicated that they had learned a particular phrase or relationship,” UA said.

“The infants who did not sleep after the sessions still recognized the phrases they had learned earlier,” UA said. “But those babies who had slept in between sessions were able to generalize their knowledge of sentence structure to draw predictive relationships to the new phrases.

“This suggests that napping supports abstract learning–that is, the ability to detect a general pattern contained in new information.”

Nap within four hours

In follow-up work, the UA researchers have shown that infants must have their naps within four hours of listening to the artificial language in order for them to demonstrate this beneficial abstraction effect. Those who failed to nap within that time, but slept normally that evening, failed to show the abstraction effect the next day, the university said.

“It’s a fairly nuanced story,” Nadel said. “What we know is that infants have mostly REM sleep, given the type of sleep they have, given how their brains are developed at that point. And they have to get some of that sleep within a reasonable amount of time after inputting information in order to be able to do abstracting work on it.

“If they don’t sleep within four to eight hours, they probably just lose the entire thing,” he said.

What this should reinforce for parents, he said, is that while it obviously is important to give infants and young children the kind of stimulation that comes from reading, talking and exposing them to lots of words, those stimuli need to happen within the context of a reasonably well-regulated daily cycle that includes adequate sleep.


NGS stock photo by W.E. Garrett