Extensive practice improves adaptation to predictable perturbations in a sequential coincident timing task

摘要

The levels of learning in motor tasks have been investigated by means of extensive practice (i.e., practice that is continued beyond the achievement of performance stabilization), which shows better performance than practice until performance stabilization when facing situations that require adaptation. However, the better performance of extensive practice has been tested with unpredictable perturbation, in which changes are necessary after the movement onset, but not with predictable perturbation, which allows planning a new organization of the action before the movement onset. The present study investigated adaptation to predictable perturbation, comparing no performance stabilization at all, practice until performance stabilization and practice beyond performance stabilization, i.e., extensive practice, in a coincident timing task. This task required the performance of a sequence of movements in accordance with a visual stimulus. Forty-five self-reported right-handed volunteers participated in this study, and they were randomly divided into three groups during the first phase of the study: Pre-Stabilization (PG), Stabilization (SG) and Extensive Practice (EG), which were operationally defined as 10 trials, three trials in a row with absolute error (AE) ≤ 30 msec and six blocks of three trials in a row with AE ≤ 30 msec, respectively. In the second phase, the velocity of the visual stimulus changed, causing a perceptual perturbation. The results showed that adaptation is easier after performance stabilization and that the variability observed after performance stabilization could be a source of adaptability. In general, these results indicate that the process of motor learning continues beyond performance stabilization.