Gradual increment on practice variability: effects on structure learning and skill parametrization

Abstract

Traditionally, on the learning of motor skill practice has been scheduled in constant, blocked, serial or random fashion. A superiority of variable over constant practice has been suggested as well as random and serial practices over blocked practice. Recently a specificity of the type of practice has been observed: constant practice helps the formation of a movement structure, especially in the early learning, and the variable practice improves parameterization. This study investigated different practice schedules and their combinations in a sequence that provides a gradual increment of variability (constant, blocked, and random) in the acquisition of motor skills. Participants were divided into four groups (n = 10): CCC [constant), BBB (blocked), RRR (random) and CBR (constant-blocked-random). The experiment consisted of an acquisition phase and a transfer test. In the acquisition phase the task comprised pressing a numeric keyboard in a given sequence (2, 8, 6, 4) with the index finger, with fixed relative timing among presses (22.2%, 44.4% and 33.3%) and specific total times (700, 900 and 1100 ms) determined by the experimental design. The test results showed a superiority of CBR and RRR groups in the absolute error measure, of CCC and BBB groups in the relative error measure, and CCC, BBB and CBR groups in the variability of relative error measure. These results evidence the practice schedules that provided smaller variability led to the learning of a movement structure, whereas the ones that provided greater variability culminated in the improvement in parameterization.