August 21, 2013
Need To Improve A Skill? Sleep On It!
Brett Smith for redOrbit.com - Your Universe Online
Having trouble learning to play the piano or improving your typing speed? You may want to sleep on it. According to a new study from Brown University and Massachusetts General Hospital, one of the brain's learning centers is highly active during sleep and could be the reason why it seems to aid in the learning process."The mechanisms of memory consolidations regarding motor memory learning were still uncertain until now," said Masako Tamaki, a postdoctoral researcher at Brown University's Laboratory for Cognitive and Perceptual Learning and co-author of the study that was published today in the Journal of Neuroscience. "We were trying to figure out which part of the brain is doing what during sleep, independent of what goes on during wakefulness. We were trying to figure out the specific role of sleep."
Previous research has shown that sleep assists in learning fine motor tasks, but neuroscientists haven't understood the mechanics behind how this works. Study co-author Yuka Sasaki speculated that sleep makes more energy available or lowers distractions, allowing for the brain to consolidate learning activities.
"Sleep is not just a waste of time," said Sasaki, a research associate professor in Brown's Department of Cognitive, Linguistic & Psychological Sciences.
In the study, nine participants slept during their preferred times while their brains were scanned with magnetoencephalography (MEG), which measures brain oscillations, and polysomnography (PSG), which tracks sleep phase. These first few nights provided baseline brain reading measurements and allowed subjects to become acclimated to the university’s sleep lab.
On the fourth day, the group of subjects was instructed to learn a finger-tapping routine on their non-dominant hand. They were then allowed to sleep for three hours, during which the subjects were scanned with PSG and MEG. An hour after waking up, the participants were asked again to perform the tapping routine, which they did faster and more accurately than the control group of six participants who did not sleep after learning the task.
On the fifth day, the neuroscientists mapped participants’ brain anatomy with a magnetic resonance imaging (MRI) machine to determine where brain oscillations they had observed with MEG were located.
Sasaki said she expected the most important activity to take place in the "M1" region of the brain, which is responsible for motor control. However, the team noted that major changes occurred in the supplementary motor area (SMA), located on the top-middle of the brain, on the opposite side of the trained hand.
The scientists noted that their observed brain oscillations significantly fit two key criteria: they changed significantly after subjects had been trained and the magnitude of that change related with the degree of the subject's improvement on the task.
After performing the experiments, study researchers moved from MGH to a newly created sleep lab at Brown. Their current work focuses on studying how the brain consolidates learning. Instead of using motor skills to understand learning, the team is now looking at visual learning tasks.
"Will we see similar effects?" Sasaki asked. "Would it be with similar frequency bands and a similar organization of neighboring brain areas?"