Richard A. Schmidt
Richard A. Schmidt
Jeffrey P. Broker, Robert J. Gregor, and Richard A. Schmidt
This study evaluated the retention of a cycling kinetic pattern using two different feedback schedules and evaluated the potential for feedback dependency in a continuous-task learning environment. Eighteen inexperienced cyclists rode a racing bicycle mounted to a fixed-fork Velodyne Trainer, with pedal forces monitored by dual piezoelectric transducers. Subjects received right-pedal shear force feedback and a criterion pattern emphasizing “effective” shear. Concurrent feedback (CFB) subjects received concurrent feedback 140 ms after the completion of every other revolution, while summary feedback (SFB) subjects received averaged feedback between trials. All subjects performed 10 retention trials without feedback 1 week later. Both groups improved significantly during practice, and performance decay in retention was negligible. Group differences during all phases were not significant. High CFB group proficiency in retention indicated that the detrimental aspects of frequent feedback were not significant. High SFB proficiency in retention suggests that large changes in kinetic patterning are achievable with relatively few feedback presentations.
Katherine M. Keetch, Timothy D. Lee, and Richard A. Schmidt
Recent evidence suggests that massive amounts of practice of the basketball free throw (a “set shot”) results in the development of a specific memory representation that is unique to this one shot distance and angle, and that is distinct from set shots taken at locations other than the free throw line. We termed this unique capability an especial skill. In this article, we review the evidence and provide new data regarding the existence of especial skills. These findings are discussed in terms of their implications for motor control theory and in terms of the broader context of specificity versus generality in the learning of motor skills.
Douglas E. Young, Doris Trachtman, Irving S. Scher, and Richard A. Schmidt
The timing of glove movements used by baseball pitchers to catch fast approaching balls (i.e., line drives) was examined in two tests to determine the responses and temporal characteristics of glove movements in high school and college baseball pitchers. Balls were projected toward the head of participants at 34.8 m·s–1 (78 mph) on average in an indoor test and at speeds approaching 58.1 m·s–1 (130 mph) in a field test. Pitchers caught over 80% and 15% of the projected balls in the indoor and field tests, respectively. Analyses of glove responses indicated that all pitchers could track the line drives and produce coordinated glove movements, which were initiated 160 ms (± 47.8), on average, after the ball was launched. College pitchers made initial glove movements sooner than high school pitchers in the field test (p = 0.012). In contrast, average glove velocity for pitchers increased from 1.33 (± 0.61) to 3.45 (± 0.86) m·s–1 across the tests, but did not differ between experience levels. Glove movement initiation and speed were unrelated, and pitchers utilized visual information throughout the ball's flight to catch balls that approached at speeds exceeding the estimated speeds in competitive situations.