REM sleep boosts memory, creativity, and more, experts announce.
In a new study, people who took naps featuring REM sleep -in which dreams are most vivid – performed better on creativity-oriented word problems. That is, the REM, or rapid eye passage, sleep helped people combine thoughts in new ways, according to psychiatrist Sara Mednick, who lead this study.
At midday, after the first round, the subjects were given a 90-minute rest period, all through which they were monitored. Some participants took naps with REM sleep, which typically starts more than an hour after a person falls asleep. Others took an REM-less nap. A third group rested quietly but didn’t sleep.
There was a second round of tests in the afternoon. In a typical second-round test, participants were questioned to guess what single word is associated with three seemingly unrelated words. For example, given “cookie,” “heart,” and “sixteen,” the answer would have been “sweet.” The right answers to many of the second-round questions were the same as the solutions to analogy questions from round one.
On the second-round questions whose answers matched first-round answers—for example, “sweet” and “sweet”—the REM nappers improved their performances by 40 percent. Non-REM nappers and the non-nappers showed no improvement on these problems, said Mednick, of the University of California, San Diego, who presented her findings Friday in San Diego at the American Psychological Family tree once a year convention.
That means that REM sleep improved participants’ ability to see relations among seemingly unrelated things: the answers from the first-round analogy problems and the three words in each round-two association test, she said.
Mednick noted that all groups remembered the morning’s answers equally well—proving that the second round wasn’t just testing nappers’ memorization abilities. Instead, REM “plays a role in selection people detach their memory of that word from being able to use that word in other contexts,” she said.
Sleep Helps Turn Memories Into Predictions?
Boosted by deep sleep, an improved memory may have yet one more subsidy: selection you imagine—and better plot for—the future.
“When you imagine future events, you’re recombining aspects of experiences that have in fact occurred,” Harvard psychiatrist Daniel Schacter, whose research was separate from Mednick’s, told National Geographic News.
Schacter, who also presented Friday at the psychology convention, has found that the same areas in the brain that handle memory, such as the hippocampus, show increased activity when subjects are questioned to imagine future events (interactive brain map).
Could REM sleep turn you into a crystal ball?
“Nobody really knows,” he said. “But I suspect there might be a connection. After all, dreams are a different way of recombining aspects of past experience.”
Source: National Geographic