Effects of early and late rest intervals on performance and consolidation of a keyboard sequence

I designed two experiments to study the extent to which 5-minute rest intervals placed early and late during practice influence motor sequence learning. In Experiment 1, 26 nonmusicians practiced a 5-note sequence with their left (non-dominant) hand on a digital piano, repeating the sequence “as quickly and accurately as possible” during 6 30- second practice blocks alternating with 30-second pauses. The training sessions for half the participants included an extended rest interval of 5 minutes between Blocks 3 and 4. Following a night of sleep, all participants performed the sequence in 6 30-second blocks with a 5-minute rest interval between Blocks 3 and 4. I found no significant differences attributable to rest condition in the number of correct key presses per block (CKP/B) during training or retest. In Experiment 2, 36 nonmusicians performed the same 5-note sequence over 12 30-second blocks alternating with 30-second pauses. One group (N = 12) rested for 5-minutes between Blocks 3 and 4 (early rest); another group (N = 12) between Blocks 9 and 10 (late rest); and a control group (N = 12) performed the 12 blocks without an extended rest interval. All were retested following a night of sleep in a procedure identical to the retest in Experiment 1. The introduction of extended rest in the early and late stages of practice significantly affected the rates of learning within and between sessions. Immediately following the 5-minute rest intervals, participants showed large gains in CKP/B, but only following the early rest did participants continue to show large gains across the next two blocks of practice. Participants in the early rest group also showed the largest overnight gains between training and retest. These findings suggest that neurophysical processes that occur during 5-minute rest intervals enhance performance and that the temporal placement of rest in a training session affects subsequent motor sequence learning and the consolidation of procedural memories.