Charles H. Shea

The automaticity of complex motor skill learning as a function of attentional focus

The present experiment was designed to test the predictions of the constrained-action hypothesis. This hypothesis proposes that when performers utilize an internal focus of attention (focus on their movements) they may actually constrain or interfere with automatic control processes that would normally regulate the movement, whereas an external focus of attention (focus on the movement effect) allows the motor system to more naturally self-organize. To test this hypothesis, a dynamic balance task (stabilometer) was used with participants instructed to adopt either an internal or external focus of attention. Consistent with earlier experiments, the external focus group produced generally smaller balance errors than did the internal focus group and responded at a higher frequency indicating higher confluence between voluntary and reflexive mechanisms. In addition, probe reaction times (RTs) were taken as a measure of the attention demands required under the two attentional focus conditions. Consistent with the hypothesis, the external focus participants demonstrated lower probe RTs than did the internal focus participants, indicating a higher degree of automaticity and less conscious interference in the control processes associated with the balance task.

Principles derived from the study of simple skills do not generalize to complex skill learning

We review research related to the learning of complex motor skills with respect to principles developed on the basis of simple skill learning. Although some factors seem to have opposite effects on the learning of simple and of complex skills, other factors appear to be relevant mainly for the learning of more complex skills. We interpret these apparently contradictory findings as suggesting that situations with low processing demands benefit from practice conditions that increase the load and challenge the performer, whereas practice conditions that result in extremely high load should benefit from conditions that reduce the load to more manageable levels. The findings reviewed here call into question the generalizability of results from studies using simple laboratory tasks to the learning of complex motor skills. They also demonstrate the need to use more complex skills in motor-learning research in order to gain further insights into the learning process.

Motor skill learning and performance: a review of influential factors

Objectives  Findings from the contemporary psychological and movement science literature that appear to have implications for medical training are reviewed. Specifically, the review focuses on four factors that have been shown to enhance the learning of motor skills: observational practice; the learner’s focus of attention; feedback, and self‐controlled practice.

Enhancing motor learning through external-focus instructions and feedback

Abstract The study examined the generalizability of the learning advantages produced by instructions that induce an external relative to an internal focus of attention (e.g., Wulf, G., Hos, M., & Prinz, W. (1998). Instructions for motor learning: Differential effects of internal versus external focus of attention. Journal of Motor Behavior , 30 , 169–179 .) to the feedback provided to the learner. Four groups of participants practiced to maintain their balance on a stabilometer. Two of these groups were instructed to either focus on their feet (internal focus) or on markers attached to the stabilometer platform (external focus), while two other groups received concurrent feedback about their deviations from the horizontal on a computer screen and were informed that the feedback represented either their feet (feedback/internal focus) or the markers (feedback/external focus). Both external focus of attention and feedback enhanced learning, as measured by a delayed retention test without feedback. Thus, the learning benefits of an external attentional focus seem to generalize to the feedback given to the learner. In addition, feedback generally enhanced performance and learning, suggesting that one function of feedback might be to promote an external focus of attention.

Attention and Motor Performance: Preferences for and Advantages of an External Focus

Abstract This study examined individual differences in the preference for and effectiveness of the type of attentional focus for motor learning. In two experiments, participants practicing a balance task (stabilometer) were asked to find out whether focusing on their feet (internal focus) or on two markers in front of their feet (external focus) was more effective. In Experiment 1, participants switched their attentional focus from trial to trial on Day 1 and used their preferred attentional focus on Day 2. In Experiment 2, participants were free to switch their attentional focus any time during 2 days of practice. Retention tests were performed on Day 3. Most participants chose an external focus. Also, they were more effective in retention than participants who preferred an internal focus.

Frequent feedback enhances complex motor skill learning.

Feedback frequency effects on the learning of a complex motor skill, the production of slalom-type movements on a ski-simulator, were examined. In Experiment 1, a movement feature that characterizes expert performance was identified. Participants (N = 8) practiced the task for 6 days. Significant changes across practice were found for movement amplitude and relative force onset. Relative force onset is considered a measure of movement efficiency; relatively late force onsets characterize expert performance. In Experiment 2, different groups of participants (N = 27) were given concurrent feedback about force onset on either 100% or 50% of the practice trials; a control group was given no feedback. The following hypothesis was tested: Contrary to previous findings concerning relatively simple tasks, for the learning of a complex task such as the one used here, a high relative feedback frequency (100%) is more beneficial for learning than a reduced feedback frequency (50%). Participants practiced the task on 2 consecutive days and performed a retention test without feedback on Day 3. The 100% feedback group demonstrated later relative force onsets than the control group in retention; the 50% feedback group showed intermediate performance. The results provide support for the notion that high feedback frequencies are beneficial for the learning of complex motor skills, at least until a certain level of expertise is achieved. That finding suggests that there may be an interaction between task difficulty and feedback frequency similar to the interaction found in the summary-KR literature.

Physical and Observational Practice Afford Unique Learning Opportunities

Abstract In 2 experiments, the authors studied the effectiveness of physical and observational practice on learning and the effect on learning of combining physical practice and observation, as compared with providing physical practice alone. In Experiment 1, retention and transfer performance of 30 university students after physical, observational, or no practice were contrasted. Consistent with findings from other studies, the retention results indicated that observational practice is inferior to physical practice. The transfer data indicated no differences between observation and physical practice groups. In Experiment 2, retention and transfer performance of 30 participants in physical and combined (alternating physical and observational) practice groups were contrasted. The retention results showed no differences between the combined and physical practice groups, but the combined group performed significantly better than the physical practice group on the transfer test. Those findings suggest that a combination of observation and physical practice permits unique opportunities for learning beyond those available via either practice regimen alone.

Specificity and Variability of Practice

The specificity of learning principle proposes that motor skills are specific and only superficially resemble other similar skills or variations of the same skill. On the other hand, the variability of practice hypothesis derived from schema theory proposes that experiences with task variations are vital to the development of the memories (schemata) responsible for response production and learning. This paper contrasts these two positions in two experiments aimed at determining the influence of providing variable and/or specific acquisition experiences on the retention of a force production task. The results clearly indicated that acquisition practice with variations of the criterion task leads to better retention than practice on the criterion task alone. This finding is contrary to a strict interpretation of the specificity of learning principle and suggests that paradigms investigating schema notions should be expanded to include potential impacts of variability of practice on tasks experienced during acquisition.

Schema Theory: A Critical Appraisal and Reevaluation

The authors critically review a number of the constructs and associated predictions proposed in schema theory (R. A. Schmidt, 1975). The authors propose that new control and learning theories should include a reformulated (a) notion of a generalized motor program that is not based on motor program but still accounts for the strong tendency for responses to maintain their relative characteristics; (b) mechanism or processes whereby an abstract movement structure based on proportional principles (e.g., relative timing, relative force) is developed through practice; and (c) explanation for parameter learning that accounts for the benefits of parameter variability but also considers how variability is scheduled. Furthermore, they also propose that new theories of motor learning must be able to account for the consistent findings spawned as a result of the schema theory proposal and must not be simply discounted because of some disfavor with the motor program notion, in general, or schema theory, more specifically.

Spacing practice sessions across days benefits the learning of motor skills

The effects of distributing practice sessions across days, compared to within days, on the learning of motor skills were examined. In Experiment 1, a continuous dynamic balance task was practiced in two sessions of seven trials each. For one group, sessions were separated by 20 min while for the other group the sessions were separated by 24 h. In Experiment 2, three variations of a key-press timing task were practiced in three sessions, one session for each task variation. Again, practice for one group was distributed within days and the other across days. In both experiments, a retention test was administered 24 h after the completion of practice. The results indicated that spacing practice sessions over relatively long intervals (days) resulted in the enhancement of performance during the remaining practice sessions and enhanced learning as assessed by the delayed retention test. The results are consistent with the memory consolidation hypothesis and suggest that this interval may play a substantial role in the learning of motor skills.