The University of California presented the study findings at the annual meeting of the American Association for the Advancement of Science in San Diego. The study recruited 39 healthy young adults and divided them into two groups, 20 of whom slept for 90 minutes between the two learning sessions and 19 who did not. All 39 were asked to learn 100 names and faces at noon, and then to learn a different set of names and faces at 6 p.m. But 20 of the volunteers who slept for 90 minutes between the two learning sessions improved their scores by 10 percent on average after sleeping; the scores of those who didn’t nap actually dropped by 10 percent.
This study supports the hypothesis that sleep, specifically the first 70-to-90-minute stage of sleep clears out the hippocampus, the area for short-term memory.
“It is like the ‘general inbox’ of your brain is full of messages,” said Bryce Mander, a postdoctoral fellow at UC Berkeley who was part of the research team, in an e-mail. “You need to clear it out before you can get more messages. That is where we believe sleep may come to the rescue.”
This study thus concludes that a bi-phasic sleep schedule, i.e., a good night’s sleep and a solid midday siesta, could increase intelligence.
Written by Snigdha Taduri