GENERALIZED MOTOR PROGRAM (GMP) LEARNING - EFFECTS OF REDUCED FREQUENCY OF KNOWLEDGE OF RESULTS AND PRACTICE VARIABILITY

The effects of reduced frequency of presentation of relative-timing kn owledge of results (KR) on constant and serial practice and whether re sponse stability is associated with increased generalized motor progra m (GMP) learning were examined. Participants (N = 40) were asked to se quentially depress 4 keys (2, 4, 8, and 6) on the numeric pad portion of the computer keyboard by using the index fingers of their right han ds. The frequency (50% and 100%) with which relative-timing KR was pre sented was manipulated in constant and in serial practice conditions. The tasks used in both the constant and the serial conditions had the same relative-timing structure, but serial practice had 3 different ab solute-timing requirements. The results, which indicated that reduced KR frequency enhances GMP learning in the serial practice condition, r eplicate the findings of Wulf, Lee, and Schmidt (1994). The reduced fr equency of KR effect was not evident for the constant practice groups, however. More interesting was the finding that constant practice was significantly better than serial practice for the development and lear ning of the GMP. The data also showed that after either constant pract ice or reduced frequency of KR, response stability was enhanced in com parison with the stability of responses following serial practice and frequent KR. Those findings suggest that when response stability is im proved either by reducing the frequency with which KR is presented or by reducing the number of task variations practiced, the development o f the GMP is enhanced but parameter specification in transfer tasks te nds to be degraded.