Amid mounting evidence of the important relationship between sleep and motor learning, researchers at the University of Montreal have identified areas of the brain that are critical in training the body's movements and found these regions communicate better after a good night's sleep.
Although sleep is well-known in the scientific community to aid motor learning, no prior understanding as to why had been explained.
Researchers studied piano players to find out more about the subcortical regions of the brain.
"The subcortical regions are important in information consolidation, especially information linked to a motor memory trace," said Karen Debas, neuropsychologist at the University of Montreal and leader author of the study.
According to Dr. Debas, simultaneous activation of the subcortical regions occurs with increased synchrony after sleep and sub-optimally after no period of sleep, regardless of whether the piano player in question was tired.
No pianos were involved in the study, but the researchers taught a group of participants a new sequence of piano-type finger movements on a box.
Participants were attached to fMRI machines during mock concerts before and after a period of sleep, and a separate control group was twice-tested without a period of sleep.
Having previously identified the putaman, a central part of the brain, to be more active after sleep, and having noted an improved performance after sleep rather than after a long passage of time during the day, researchers knew they were onto something.
Applying the technique of brain connectivity analysis, which identifies simultaneously activated regions and assesses whether they are communicating with each other and how much, they were able to pinpoint the subcortical regions, which include the putaman, as being the most intricately integrated.
"After a night of sleep, we found that this network was more integrated than the others, that is, interaction among these regions was greater when consolidation had occurred," says Debas. "A night of sleep seems to provide active protection of this network, which the passage of daytime does not provide. Moreover, only a night of sleep results in better performance of the task."
The study was published in the journal NeuroImage.
Sleep as a means of reinforcing learning has been oft explored and notable advancements as of late include a New York University-based paper that breaks down the process using mice, published in the journal Science.
"Our data suggest that neuronal reactivation during sleep is quite important for growing specific connections within the motor cortex," said senior investigator Wen-Biao Gan, PhD.
