Musicians who learn a new melody demonstrate enhanced skills after a night's sleep, according to a new study. Researchers from the Southern Methodist University, Dallas found that performance of a musical task improved among pianists whose practice of a new melody was followed by a night of sleep. However, that when two similar melodies were practiced one after the other, followed by sleep, any gains in speed and accuracy achieved during practice diminished overnight, said Sarah E Allen, an assistant professor of music education in SMU's Meadows School of the Arts. "The goal is to understand how the brain decides what to keep, what to discard, what to enhance, because our brains are receiving such a rich data stream and we don't have room for everything," Allen said. Surprisingly, in a third result the study found that when two similar musical pieces were practiced one after the other, followed by practice of the first melody again, a night's sleep enhanced pianists' skills on the first melody. "The really unexpected result that I found was that for those subjects who learned the two melodies, if before they left practice they played the first melody again, it seemed to reactivate that memory so that they did improve overnight. Replaying it seemed to counteract the interference of learning a second melody," she said. The study adds to a body of research in recent decades that has found the brain keeps processing the learning of a new motor skill even after active training has stopped. Sixty undergraduate and graduate music majors participated in the research.
Divided into four groups, each musician practiced either one or both melodies during evening sessions, then returned the next day after sleep to be tested on their performance of the target melody. Musicians who learned a single melody showed performance gains on the test the next day. Those who learned a second melody immediately after learning the target melody didn't get any overnight enhancement in the first melody. Those who learned two melodies, but practiced the first one again before going home to sleep, showed overnight enhancement when tested on the first melody. The study will be published in the journal Psychology of Music.