Suzete Chiviacowsky

Feedback After Good Trials Enhances Learning

Recent studies (Chiviacowsky & Wulf, 2002, 2005) have shown that learners prefer to receive feedback after they believe they had a “good” rather than “poor”trial. The present study followed up on this finding and examined whether learning would benefit if individuals received feedback after good relative to poor trials. Participants practiced a task that required them to throw beanbags at a target with their nondominant arm. Vision was prevented during and after the throws. All participants received knowledge of results (KR) on three trials in each 6-trial block. While one group (KR good) received KR for the three most effective trials in each block, another (KR poor) received feedback for the three least effective trials in each block. There were no group differences in practice. However, the KR good group showed learning advantages on a delayed retention test (without KR). These results demonstrated that learning is facilitated if feedback is provided after good rather than poor trials. The findings are interpreted as evidence for a motivational function of feedback.

Learning benefits of self-controlled knowledge of results in 10-year-old children.

Self-controlled knowledge of results (KR) refers to a type of KR in which the learner actively chooses when to receive information about the outcome of his or her performance. That is, the learner is required to make a decision about whether or not he or she wants to receive KR after a trial. This approach differs from that used in most KR studies, in which the experimenter controls the frequency and schedule of KR delivery. Studies on self-efficacy perception (Bandura, 1977, 1993), strategies of self-regulated learning (Chen & Singer, 1992; Zimmerman & Ponz, 1986), and academic learning (Winne, 1995) have shown that learners’ ability to use cognitive or behavioral strategies in a self-controlled practice context enhances their performance and learning. In the motor learning area, Janelle and collaborators (Janelle, Kim, & Singer, 1995; Janelle, Barba, Frehlich, Tennant, & Cauraugh, 1997) were the first to adopt this approach by examining the effectiveness of self-controlled KR schedules. Using a novel throwing task, Janelle et al. (1997) allowed one group of learners to decide when to receive feedback about movement form. The self-control group showed clear learning advantages compared to those in the yoked group, in which each participant was yoked to one in the self-control group with regard to when KR was or was not provided. Although the feedback schedule was identical for both groups, providing learners the opportunity to decide when they wanted to receive feedback was more beneficial than externally controlled (yoked) feedback. The self-control group also showed superior learning compared to other groups with experimentercontrolled feedback schedules (e.g., summary KR). Learning benefits have also been found for other types of self-controlled practice, such as using assistive devices (i.e., ski poles) in learning a ski simulator task (Wulf, Clauss, Shea, & Whitacre, 2001; Wulf & Toole, 1999) and observational practice for learning basketball free-throw shooting (Wulf, Raupach, & Pfeiffer, 2005). The self-control benefits for learning appear to be a robust phenomenon. However, previous studies have exclusively used adults as participants. Thus, it is unclear whether the effects of this variable generalize to different motor development levels. An interesting question is whether children would also benefit from self-controlled practice. A potentially limiting factor in generalizing this effect to children lies in their information-processing capabilities. A number of studies suggested there are differences between children and adults in their capability to process information (e.g., Badan, Hauert, & Mounoud, 2000; Chi, 1977; Connolly, 1970, 1977; Lambert & Bard, 2005). According to Connolly (1970), changes in motor development during childhood can be attributed to two classes of variables. The first refers to “hardware” changes that occur as a function of growth. This includes such physical changes as increased strength and height as well as central nervous system changes, all of which are considered structural. The second is related to “software” changes and pertains to improvements in the capacity to use the structures. These are considered cognitive, and they occur as a consequence of developing processing-information capabilities (Connolly, 1977; Thomas, 1980). Learning Benefits of Self-Controlled Knowledge of Results in 10-Year-Old Children

An external focus of attention enhances balance learning in older adults

Studies with young adults have shown that an external focus of attention (i.e., on the movement effect) results in more effective motor learning and greater automaticity than an internal focus (i.e., on ones own body movements). The present study examined whether instructions inducing an external versus internal attentional focus would differentially affect the learning of a balance task in 32 older adults (24 females and 8 males, mean age: 69.4 years), divided equally, by number and gender, into two groups. The task required participants to stand on a balance platform (stabilometer) tilting to the left and right, and to try to keep the platform as close to horizontal as possible during each 30-s trial. The external focus group was instructed to concentrate on keeping markers on the platform horizontal, while the internal focus group was instructed to concentrate on keeping their feet horizontal. The dependent variable was time in balance (i.e., platform movements within ± 5°). Participants performed 10 practice trials on day 1, with focus reminders given before each trial. Learning was assessed by a retention test, consisting of five trials without instructions, performed 1 day later. The external focus group outperformed the internal focus group in retention [F(4, 120)=3.46, p=.01]. The results demonstrate that the learning benefits of an external attentional focus are generalizable to older learners.

Frequent External-Focus Feedback Enhances Motor Learning

The present study examined the hypothesis that feedback inducing an external focus of attention enhances motor learning if it is provided frequently (i.e., 100%) rather than less frequently. Children (10- to 12-year-olds) practiced a soccer throw-in task and were provided feedback about movement form. The feedback statements, provided either after every (100%) or every third (33%) practice trial, were similar in content but induced either an internal focus (body-movement related) or external focus (movement-effect related). The results demonstrated that learning of the movement form was enhanced by external-focus feedback after every trial (100%) relative to external-focus feedback after every third trial (33%) or internal-focus feedback (100%, 33%), as demonstrated by immediate and delayed transfer tests without feedback. There was no difference between the two internal-focus feedback groups. These findings indicate that the attentional focus induced by feedback is an important factor in determining the effectiveness of different feedback frequencies. We argue that the informational properties of feedback cannot sufficiently account for these and related findings, and suggest that the attentional role of feedback be given greater consideration in future studies.

Normative Feedback Effects on Learning a Timing Task

This study investigated the influence of normative feedback on learning a sequential timing task. In addition to feedback about their performance per trial, two groups of participants received bogus normative feedback about a peer groups average block-to-block improvement after each block of 10 trials. Scores indicated either greater (better group) or less (worse group) than the average improvement, respectively. On the transfer test 1 day later, which required producing novel absolute movement times, the better group demonstrated more effective learning than the worse group. These findings add to the mounting evidence that motivational factors affect motor skill learning.

Knowledge of Results After Good Trials Enhances Learning in Older Adults

In recent years, some researchers have examined motor learning in older adults (e.g., Carnahan, Vandervoort, & Swanson, 1996; Daselaar, Rombouts, Veltman, Raaijmakers, & Jonker, 2003); Smith et al., 2005; Wishart & Lee, 1997). Some of these studies have specifically looked at the effectiveness of different manipulations of extrinsic feedback, or knowledge of results (KR). While in young adults decreasing the “usefulness” of feedback often enhances learning (for reviews, see Schmidt, 1991; Swinnen, 1996; Wulf & Shea, 2004), this evidence appears to be somewhat mixed for older adults. While some studies found similar effects of different KR manipulations for younger and older adults (e.g., Carnahan et al., 1996; Swanson & Lee, 1992), others did not find unqualified benefits of making KR more difficult to use for learning in older adults (e.g., Behrman, Vander Linden, & Cauraugh, 1992; Wishart & Lee, 1997; Wishart, Lee, Cunningham, & Murdoch, 2002). In the study by Carnahan et al. (1996), for example, older adults (average age: 75.0 years) practiced a computer-keypressing task with a specified goal time. KR was provided either in a summary format, where KR about each trial was provided only after the completion of a given block of trials, or after every single trial. Similar to what studies with younger adults have shown (e.g., Gable, Shea, & Wright, 1991; Schmidt, Young, Swinnen, & Shapiro, 1989; Schmidt, Lange, & Young, 1990; Yao, Fischman, & Wang, 1994), summary KR resulted in more effective retention performance than did KR provided after every trial. In contrast, other studies did not find learning advantages of more “difficult” KR manipulations, such as reduced KR frequencies, for motor skill learning in older adults (e.g., Behrman et al., 1992; Wishart & Lee, 1997; Wishart, Lee, Cunningham, & Murdoch, 2002). Behrman et al. (1992) used a task that required participants (average age: 69 years) to reproduce a force-time curve, presented on an oscilloscope, by modulating isometric force production of their right elbow extensors. Similar to what Vander Linden, Cauraugh, and Greene (1993) found for young adults using a similar task, concurrent knowledge of performance (KP) was not beneficial to learning, compared to terminal KP (100% or 50%). However, the 50% KP condition did not result in more effective learning than the 100% condition, contrary to Vander Linden et al.’s (1993) findings. Furthermore, Wishart and Lee (1997) did not find differential learning effects as a function of different KR frequencies (100% versus 67%) for older adults (average age: 66.2 years) on a task that required participants to produce a continuous movement comprising three distinct spatial segments with specific timing requirements (although no KR frequency effects were found for younger participants [average age: 19.8 years] either). In the Wishart et al. (2002) study, younger (19–27 years) and older (65–70 years) participants practiced a bimanual coordination task under concurrent or reduced feedback conditions. Older participants not only performed generally less effectively than younger participants, but they also benefited more from concurrent feedback relative to terminal feedback. Finally, in Van Dijk and Hermens’ study (2006), younger adults (20–35 years) were able to utilize myofeedback (i.e., display of electromyographic signal) in a task requiring them to lower trapezius muscle activity, whereas older adults (55–70 years) were not. Knowledge of Results After Good Trials Enhances Learning in Older Adults

Motor learning benefits of self-controlled practice in persons with Parkinson's disease

The present study examined the effectiveness of a training method to enhance balance in people with PD, which could potentially reduce their risk for falls. Specifically, we investigated whether the benefits of the self-controlled use of a physical assistance device for the learning of a balance task, found previously in healthy adults, would generalize to adults with PD. Twenty-eight individuals with PD were randomly assigned to one of two groups, a self-control and a yoked (control) group. The task required participants to stand on a balance platform (stabilometer), trying to keep the platform as close to horizontal as possible during each 30-s trial. In the self-control group, participants had a choice, on each of 10 practice trials, to use or not to use a balance pole. Participants in the yoked group received the same balance pole on the schedule used by their counterparts in the self-control group, but did not have a choice. Learning was assessed one day later by a retention test. The self-control group demonstrated more effective learning of the task than the yoked group. Questionnaire results indicated that self-control participants were more motivated to learn the task, were less nervous, and less concerned about their body movements relative to yoked participants. Possible reasons for the learning benefits of self-controlled practice, including a basic psychological need for autonomy, are discussed.

Self-Controlled Learning: The Importance of Protecting Perceptions of Competence

Recent studies examining the role of self-controlled feedback have shown that learners ask for feedback after what they believe was a “good” rather than “poor” trial. Also, trials on which participants request feedback are often more accurate than those without feedback. The present study examined whether manipulating participants’ perception of “good” performance would have differential effects on learning. All participants practiced a coincident-anticipation timing task with a self-controlled feedback schedule during practice. Specifically, they were able to ask for feedback after 3 trials in each of three 10-trial practice blocks. While one group (Self-30) was told that an error of 30 ms or less would be considered good performance, another group (Self-4) was informed that an error of 4 ms or less would be considered a good trial. A third, self-control group (Self) did not receive any information about what constituted good performance. The results showed that participants of all groups asked for feedback primarily after relatively good trials. At the end of practice, both the Self-30 and Self groups demonstrated greater perceived competence and self-efficacy than the Self-4 group. The Self-30 and Self groups also performed with greater accuracy and less variability in retention and transfer (non-dominant hand) 1 day later. The present findings indicated that the typical learning benefits of self-controlled practice can be thwarted by depriving learners of the opportunity of experiencing competence through good performance. They add to the accumulating evidence of motivational influences on motor learning.

Self-Controlled Feedback in 10-Year-Old Children: Higher Feedback Frequencies Enhance Learning

In the past few years, several studies have demonstrated the effectiveness of self-controlled practice for motor learning. These studies have examined how giving learners the opportunity to control a certain aspect of the practice conditions—such as the delivery of extrinsic feedback (e.g., Chen, Hendrick, & Lidor, 2002; Chiviacowsky & Wulf, 2002, 2005; Janelle, Kim, & Singer, 1995; Janelle, Barba, Frehlich, Tennant, & Caraugh, 1997), use of physical assistance devices (Wulf, Clauss, Shea, & Whitacre, 2001; Wulf & Toole, 1999), or demonstrations of the movement goal (Wulf, Raupach, & Pfeiffer, 2005)—affects learning. Typically, self-controlled practice conditions are compared to yoked conditions, in which each participant is yoked to one self-control participant. In the case of self-controlled feedback, for example, yoked learners received feedback on the same trials on which their self-control counterparts requested feedback. Allowing learners to control part of the practice conditions has been found to result in more effective learning, compared to predetermined (i.e., yoked) conditions. Possible reasons for those learning benefits include a more active involvement of the individual in the learning process and, in turn, deeper processing of task-relevant information (e.g., McCombs, 1989; Wulf et al., 2001) and enhanced motivation (e.g., Boekaerts, 1996; Chiviacowsky & Wulf, 2002, 2007). The percentage of trials on which participants requested feedback in previous studies was relatively low: 7% in Janelle et al. (1995; underhand ball toss at target; feedback about movement form), 11% in Janelle et al. (1997; throwing with the nondominant arm at a target; feedback about movement form), 35% in Chiviacowsky and Wulf (2002; sequential timing task; feedback about segment movement times); an exception seems to a study by Chen et al. (2002; sequential timing task; feedback about overall movement time), in which participants requested feedback on 97% of the trials. While the frequency of feedback requests might depend on various factors, such as the nature of the task or on the exact instructions given to participants (e.g., the extent they encourage the learner to ask for feedback), there is a possibility that not all learners choose the “optimal” frequency of feedback, which, in turn, might have a qualifying effect on the learning advantages of self-controlled feedback. A recent study by Chiviacowsky, Godinho, and Tani (2005) did not support this view—at least for adult learners. The authors looked at the effects of different feedback frequencies chosen by adult participants. Specifically, Chiviacowsky et al. (2005) used a sequential timing task and compared two “extreme” groups of self-control participants, namely, those who chose the highest versus the lowest frequencies of feedback during practice. That is, of the 60 (self-control) learners in their study, they compared retention performances of the 20 participants who chose the highest frequencies (i.e., 50–99%) and Self-Controlled Feedback in 10-Year-Old Children: Higher Feedback Frequencies Enhance Learning

An External Focus of Attention Enhances Motor Learning in Children with Intellectual Disabilities.

BACKGROUND The present study examined whether the learning benefits of an external focus of attention (i.e., on the movement effect) relative to an internal focus (i.e. on the movement), found previously in non-disabled children and adults would also be found in children with intellectual disabilities (IDs). METHODS Participants (n = 24; average age: 12.2 years) with mild intellectual deficiency (IQ = 51-69) practiced throwing beanbags at a target. In the external focus group, participants were instructed to direct their attention to the movement of the beanbag, while in the internal focus group, participants were asked to direct their attention to the movement of their hand. The practice phase consisted of 40 trials, and attentional focus reminders were given after every third trial. Learning was assessed 1 day later by retention and transfer (greater target distance) tests, each consisting of 10 trials. No focus reminders were given on that day. RESULTS The external focus group demonstrated more effective learning than the internal focus group, as evidenced by more accurate tosses on the transfer test. CONCLUSIONS The present findings show that instructions that induce an external focus of attention can enhance motor learning in children with IDs.