Effects of Variable Practice on Retention and Motor Schema Development in down Syndrome Subjects

Abstract

Portions of Schmidt's schema theory, the effects of variable practice on retention and ability to learn a novel motor task, were tested using Down syndrome subjects. 23 subjects ranged in mental and chronological ages from 3.0 to 5.1 yr. and 4.6 to 22 yr., respectively. IQs ranged from 32 to 62. The two throwing tasks were closed, discrete movements requiring no feedback or error detection during movement. Subjects were randomly assigned to a specific-practice, variable-practice, or control group. Specific group subjects practiced 100 trials from the test-target location. Variable-practice subjects also practiced 100 trials but from four different practice locations. The control group practiced an unrelated kicking activity. All subjects participated in identical pretests, posttests, and retention tests to assess accuracy on these throwing tasks. A standard archery target was used to score tosses. To examine the effects of practice on a novel task, two target conditions, or tasks, were employed. On Task A the subject tossed a bean bag at the archery target placed flat on the floor. For Task B, the novel task, the target was placed upright on the wall. Subjects were assigned higher scores for tosses landing closer to the center of the target. Analysis of variance indicated no significant differences between groups on Task A pretest or posttest. Significance was detected for the main effect of group for Task B. However, the Scheffé post hoc test indicated that the simple main effects were nonsignificant. This research did not support Schmidt's schema theory. However, the lack of significant differences between variable- and specific-practice conditions supports the notion that variable practice may be no less effective than specific practice in the instruction of movement skills to subjects with Down syndrome.