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Biomedical subjects

C A Wrisberg

Publications and source records attributed to C A Wrisberg.

13 recordsLinked to original sources
PubMed1997

The effect of knowledge of results delay and the subjective estimation of movement form on the acquisition and retention of a motor skill.

This study examined the effects of knowledge of results (KR) delay and subjective estimation of movement form on the acquisition and retention of a motor skill. During acquisition, four groups of participants performed 60 trials of a throwing accuracy task under the following conditions: (a) immediate KR, (b) delayed KR, (c) immediate KR + form estimation, and (d) delayed KR + form estimation. Retention tests of throwing accuracy and outcome error estimation in the absence of visual KR were administered 5 min and 24 hours following acquisition. Throwing accuracy was significantly higher during acquisition but significantly lower during retention for immediate-KR participants than for delayed-KR participants. However, participants who estimated their movement form during acquisition produced significantly higher throwing accuracy and lower estimation error during retention than those who did not.

Analysis of Variance↗
PubMed1995

The effects of augmented information on motor learning: a multidimensional assessment.

Subjects performed trials of a two-hand coordination task involving the manipulation of a small, steel ball through a maze. During the acquisition phase, control subjects received no augmented information while subjects in two experimental groups were provided with visual aids or a cognitive strategy. One day later, subjects performed under control conditions on familiar (relearning phase) and unfamiliar (transfer phase) sections of the maze. A 3 x 3 (Group x Phase) repeated measures multivariate analysis of variance revealed significant phase differences for all dependent measures but no significant group effects. Chi-square analysis of ratings of cue usage as well as postexperimental interviews suggested, however, that practice conditions differentially influenced the search strategies of subjects. Implications of the findings for contemporary theories of motor learning are discussed.

Adolescent↗
PubMed1993

A field test of the activity-set hypothesis for warm-up decrement in an open skill.

To determine the relative effectiveness of different warm-up activities in eliminating postrest warm-up decrement (WUD), 65 highly skilled tennis players performed 60 forehand and 60 backhand groundstrokes, rested for either 5 or 15 min, engaged in one of five interpolated activities (additional rest, running in place, imagery, practice swings, or air dribbling), and then performed 12 additional forehands and backhands. An analysis of differences between prerest and postrest arousal measures (heart rate, positive cognitive arousal, and negative cognitive arousal) revealed that all of the interpolated activities except additional rest restored arousal to levels near those found at the end of prerest trials. Postrest WUD was also eliminated by practice swings and air dribbling and, to a slightly lesser extent, by running in place. We concluded that an effective warm-up for open skills such as the tennis groundstroke should include some form of overt physical activity that direct the attention of the performer to task-relevant cues.

Adolescent↗
PubMed1991

The effect of contextual variety on the practice, retention, and transfer of an applied motor skill.

Laboratory research in motor learning has consistently demonstrated higher retention and/or transfer when practice occurs under conditions of high contextual variety (e.g., Lee & Magill, 1983; Newell & Shapiro, 1976; Shea & Morgan, 1979;). In the present study, an attempt was made to determine whether a contextual variety effect could be demonstrated in a standard physical education instructional setting. During practice trials on the long and short badminton serves, male and female subjects performed under either blocked (i.e., all trials of one serve followed by all trials of the other) or varied (i.e., alternating trials of long and short serves) conditions. Retention and transfer tests (i.e., using the service area opposite that employed during the practice phase) were administered at the end of the badminton unit. Although little difference was observed in the performance of the two groups during practice, alternating-trial subjects demonstrated significantly higher retention of the short serve and significantly higher transfer of both serves than blocked-trial subjects. The performance of male and female subjects was not differentially influenced by practice structure conditions. It was concluded that a practice schedule that requires performers to change their plan of action from trial to trial may facilitate the retention and transfer of motor skills in applied instructional settings.

Adult↗
PubMed1988

Physiological and psychological responses to exercise with an induced attentional focus.

In this study techniques were employed to induce exercising subjects to focus attention on themselves or on an external event. A total of 20 adult subjects (10 men and 10 women) were familiarized with a treadmill exercise protocol and then on two subsequent occasions performed submaximal exercise followed by a run to exhaustion under attentional conditions of self-focus (watching themselves in a mirror while listening to their breathing) and external focus (watching and listening to a movie). The order of focus conditions was counterbalanced among subjects. Analysis of postexperimental responses from subjects indicated that the procedures used to induce each type of attentional focus were successful. However, physiological and psychological responses in the two focus conditions were not always uniform for men and women, particularly during light work when men tended to have higher heart rates and significantly lower Rated Perceived Exertion while women had lower heart rates and higher Rated Perceived Exertion under self-focused conditions than under externally focused conditions. Possible explanations for the incongruence of physiological and psychological responses of men and women to the two types of attentional focus are discussed.

Adaptation, Psychological↗
PubMed1983

Receptor anticipation of mentally retarded and nonretarded adults.

The effect of stimulus velocity and information feedback on the receptor anticipation (Poulton, 1957) performance of mentally retarded and nonretarded adults was investigated. Thirty trials were given in which subjects attempted to execute a preferred-hand button press response coincident with the lighting of the last of a series of runway lamps illuminating in a pattern of apparent linear motion. Although the receptor anticipation of nonretarded adults was found to be significantly superior to that of retarded subjects, both groups responded similarly to the velocity and feedback manipulations.

Adult↗
PubMed1977

Development of a mechanism for detection of error and retention of a graded motor response.

Several methods for developing an internal mechanism for error detection were compared to determine the extent to which a self-paced response could be acquired and retained without knowledge of results. During training, blindfolded subjects attempted to learn a positioning response under one of three conditions. One group was presented with the criterion end location by means of a stop and then required to recall the location with the stop removed. A second group moved the total distance of the track and then was instructed to replace the slide in a location representing a specific fraction of the total. A final group of subjects learned the criterion location by using post-response knowledge of results administered on each trial. Following acquisition subjects were give retention trials involving only repetition of the acquired response. The development of a strong mechanism for error detection was indicated only for those groups presented with the standard or with post-response knowledge of results. During retention trials (without knowledge of results), performance of the group required to learn the criterion by estimating a fraction of the total range was characterized by significanlty greater response biasing and less consistency than the other conditions. The findings were discussed in terms of several predictions from Adams' (1971) closed-loop theory of motor learning.

Cognition↗