When less of the same is more: Benefits of variability of practice in pianists

Variability of practice has been demonstrated to have beneficial effects for motor skill acquisition, transfer, and retention. This study extends the line of research to musical practice. Pianists were trained to perform a wide interval leap on the piano with their left hand. Performance at the target distance was tested before and after a 30-minute controlled training. One group (FIX) practiced the target interval only. The other group (VAR) received variable training on four different intervals including the target. Transfer was tested on an interval novel to either group. Retention was assessed in a retest 24 hours later. Leap Distance Error (LDE) and Leap Execution Time (LET) were measured. After training, LDE improved non-significantly in both groups. In the VAR group significant improvement was seen on the next day. This was not the case in the FIX group. In contrast to the FIX group, the VAR group showed significantly faster LET after training compared to baseline, which was stable at retention. The findings are discussed with regard to predictions made by theories of motor learning and implications for musical practice.