To study the effects of gross-motor skill overlearning on retention and relearning by mild, moderate, and severe institutionalized male retardates 79 mentally retarded males were randomly assigned to a learning group or an overlearning group. Learning to throw a bean bag at a target at 8 ft. occurred when Ss accumulated 10 points in 3 consecutive throws, and at 16 ft. when 6 points were accumulated in three consecutive throws. The learning group reached criterion at one time at each distance, but the overlearning group was given three consecutive trials at criterion. All Ss were retrained after 5 wk. Trials to criterion for original acquisition and relearning indicated overlearning gave superior performance on retention.

Attention deficit disorder with hyperactivity and methylphenidate: the effects of dose and mastery level on children's learning performance. This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed. Published in Journal of abnormal child psychology (1989)