Effects of aging and reduced relative frequency of knowledge of results on learning a motor skill.

Although there is evidence for age-related changes in both cognition and motor control, very little is known about the effect of age on learning of new motor skills. The present experiment addressed the interaction between aging and the role of knowledge of results (KR) on a motor learning task. Using a three-segment task on which each segment had specific timing goals, three different manipulations of relative frequency of information about performance were compared in younger and older adults. The three conditions were (a) 100% KR in which information about performance on each segment was provided after every trial, (b) 67% KR in which the performance information was faded over trials, and (c) 67% KR in which the performance information was faded over the segments within each trial. Following 90 acquisition trials, all subjects performed retention, transfer, and reacquisition tests. There were age-related differences for movement accuracy and consistency on acquisition and on the retention tests but not on the transfer test. However, none of these differences interacted with the frequency of KR manipulations. Surprisingly, there was no effect due to the fading schedules of KR. In general, these results indicated that younger and older adults use KR in a similar way to learn a motor skill.