Practice Does Not Diminish the Role of Visual Information in On-Line Control of a Precision Walking Task: Support for the Specificity of Practice Hypothesis

Benefits of a Light-Painting Technique for Learning to Write New Characters: A Proof of Concept With Adults

Learning to write relies on the effective integration of sensory feedback and a transition from motor control based on written tracings to motor control based on expert writing movements. This study aimed to test whether the photographic technique of light painting (LP) would facilitate this transition. To achieve this, we conducted two experiments using different LP setups. LP involves moving a light source in a dark environment while taking a long-exposure photograph. LP entails both a real-time reduction of product-related visual information and a post-trial addition of process-related visual information. In the first experiment, we conducted a pre-test, training, and post-test in which 16 adults wrote four new characters with the non-dominant hand. During the training sessions, participants stood and wrote in a vertical frame (1 × 1.2 m) two characters in the control condition (with a marker on the vertical support) and two characters in the LP condition (with a flashlight in the air). In the test phases, participants were seated at a table and copied the four characters into a square (4 cm * 4 cm) on a fixed sheet of graphics paper. As in-air writing strongly differs from classical handwriting situations, we performed a second LP experiment. The aim was to implement LP training in a condition closer to writing. Sixteen new participants followed the same protocol but sat at a table and wrote in a horizontal square (20 cm * 20 cm). In both experiments, participants who trained with the LP method wrote faster and with less pressure than those trained in the control condition. We also observed an improvement in spatial accuracy in Experiment 2, whatever the training condition. LP seemed to have led participants to focus on the writing process, probably because it modified the nature and timing of the visual information used for writing. LP may be a promising technique for remediating writing difficulties.

Sensorimotor integration and motor learning during a novel visuomotor tracing task in young adults with attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that has noted alterations to motor performance and coordination, potentially affecting learning processes and the acquisition of motor skills. This work will provide insight into the role of altered neural processing and sensorimotor integration (SMI) while learning a novel visuomotor task in young adults with ADHD. This work compared adults with ADHD (n = 12) to neurotypical controls (n = 16), using a novel visuomotor tracing task, where participants used their right-thumb to trace a sinusoidal waveform that varied in both frequency and amplitude. This learning paradigm was completed in pre, acquisition, and post blocks, where participants additionally returned and completed a retention and transfer test 24 h later. Right median nerve short latency somatosensory-evoked potentials (SEPs) were collected pre and post motor acquisition. Performance accuracy and variability improved at post and retention measures for both groups for both normalized (P < 0.001) and absolute (P < 0.001) performance scores. N18 SEP: increased in the ADHD group post motor learning and decreased in controls (P < 0.05). N20 SEP: increased in both groups post motor learning (P < 0.01). P25: increased in both groups post motor learning (P < 0.001). N24: increased for both groups at post measures (P < 0.05). N30: decreased in the ADHD group and increased in controls (P < 0.05). These findings suggest that there may be differences in cortico-cerebellar and prefrontal processing in response to novel visuomotor tasks in those with ADHD.NEW & NOTEWORTHY Alterations to somatosensory-evoked potentials (SEPs) were present in young adults with attention-deficit/hyperactivity disorder (ADHD), when compared with neurotypical controls. The N18 and N30 SEP peak had differential changes between groups, suggesting alterations to olivary-cerebellar-M1 processing and SMI in those with ADHD when acquiring a novel visuomotor tracing task. This suggests that short-latency SEPs may be a useful biomarker in the assessment of differential responses to motor acquisition in those with ADHD.

Application of Feedback Type on Performance of Abdominal Drawing-In Maneuver in Healthy Adults: A Quasi-Experimental Study of Motor Control and Motor Learning

OBJECTIVE

The aim of this study was to compare the effects of verbal, tactile-verbal, and visual feedback on muscle activation of the lumbar stabilizers relative to extremity movers during an abdominal drawing-in maneuver when feedback is withheld.

METHODS

This quasi-experimental study equally divided 54 healthy adults into 3 feedback groups (verbal, tactile-verbal, and visual) who trained twice per week over a 4-week period to perform supine abdominal drawing-in maneuvers. The percentage of maximum voluntary isometric contraction of rectus abdominis, multifidus (MF), erector spinae, and hamstrings (HS) as an outcome measure was acquired using surface electromyography. A 2-way factorial analysis of variance with bootstrapping allowed for comparison of post-pre difference scores across the interaction of feedback and muscle groups.

RESULTS

Hamstring activation decreased in those receiving tactile-verbal feedback relative to an increase in participants given visual feedback. Furthermore, when using verbal feedback, HS activity increased relative to a decline in rectus abdominis, and when presenting visual feedback, HS activity increased relative to a decrease in MF. However, no post-pre changes were seen across muscles with tactile-verbal feedback.

CONCLUSION

Although tactile-verbal feedback did not increase MF recruitment, it produced less HS activity than visual feedback. Undesirable HS recruitment may reflect boredom or feedback dependency.

Seeing Is Believing: Blind Putting Drills Confer No Advantage to the Novice Golfer

Purpose: Golf coaches may recommend "blind" putting drills in which golfers close their eyes to improve their feel. Research on specificity of learning suggests, however, that adding or removing a source of sensory information after practicing under differing circumstances can cause performance decrements. Specificity of learning is also dependent upon specific task requirements. The purpose of this study was to examine whether golf putting, requiring body positioning and aiming an implement, would benefit from blind training. Method: Novice golfers (n = 24) in Vision Training (VT) & No-Vision Training (NVT) groups completed 108 trials of a 10-ft putt. After a 24-hr delay, both groups completed sighted- and blind-putting tests. Results: Acquisition results revealed Group × Block interactions in RE (p = .025) and y-VE (p = .032). Post hoc procedures revealed significant differences between the groups on Block 2 (p = .017), with the NVT group producing longer mean RE. During testing, RE and x-VE results revealed Group × Test interactions (p = .027 & .041), such that performance of the VT group suffered when transferred to blind putting, while performance of the NVT group did not differ when transferred. Conclusion: NVT did not confer any advantage for subsequent performance with vision. Moreover, results were not consistent with the specificity of learning hypothesis and suggest that putting does not rely on complete sensory integration to support subsequent performance. Presumably, task requirements related to body positioning provided adequate sensory cues for successful performance.

Effect of Visual Condition on Performance of Balance-Related Tasks in Elite Dance Students

The purpose of this study was to investigate the effects of visual condition (low light, full light, and full light with mirror) on balance control and technical form during two technical dance movements in a group of elite collegiate dance students. Dancers demonstrated higher center of pressure velocity indicating lower control while performing a static dance task (parallel relevé retiré) and a dynamic dance task (fondu relevé en croix) under low light conditions than either lighted condition. Measures of Western ballet technique (pelvic obliquity, knee extension, and ankle plantar flexion) showed no decrement under low light conditions. No effect of concurrent mirror feedback was found on either center of pressure velocity or technical requirements of the dance tasks.

Action dual tasks reveal differential effects of visual imagery perspectives on motor performance

Imagery research has identified two main visual perspectives, external visual imagery (EVI, third person) and internal visual imagery (IVI, first person). Based upon findings from brain imaging literature showing that different neural substrates are recruited for IVI and EVI perspectives, and that IVI activates motor system brain areas, we hypothesised that a concurrent action dual task would cause greater interference in performance for IVI than EVI. In a first experiment, participants were allocated to either an IVI or an EVI group, and were tasked with moving an onscreen marker towards a target in three blocked conditions: imagery, imagery with a concurrent motor dual-task of sequencing, and a math control. An interaction between imagery group and condition was driven by greater root mean square error for participants in the dual-task condition in the IVI group compared with the EVI group. We replicated the experiment with an eye-tracking objective measure of IVI; the results again showed that participants in the IVI group made more errors in motor movements, and an interference effect in eye movements, during the dual-task sequencing condition compared with the EVI group. The results of the two experiments reveal that a secondary motor task does interfere with IVI, providing behavioural evidence that IVI appears to rely on motor system processes more than EVI. These results have important implications for the use of visual imagery perspectives across a number of domains, with this paper being an essential reference for those conducting visual imagery perspectives research.

Effects of practice schedule and task specificity on the adaptive process of motor learning

This study investigated the effects of practice schedule and task specificity based on the perspective of adaptive process of motor learning. For this purpose, tasks with temporal and force control learning requirements were manipulated in experiments 1 and 2, respectively. Specifically, the task consisted of touching with the dominant hand the three sequential targets with specific movement time or force for each touch. Participants were children (N=120), both boys and girls, with an average age of 11.2years (SD=1.0). The design in both experiments involved four practice groups (constant, random, constant-random, and random-constant) and two phases (stabilisation and adaptation). The dependent variables included measures related to the task goal (accuracy and variability of error of the overall movement and force patterns) and movement pattern (macro- and microstructures). Results revealed a similar error of the overall patterns for all groups in both experiments and that they adapted themselves differently in terms of the macro- and microstructures of movement patterns. The study concludes that the effects of practice schedules on the adaptive process of motor learning were both general and specific to the task. That is, they were general to the task goal performance and specific regarding the movement pattern.

The specificity of practice hypothesis in goal-directed movements: visual dominance or proprioception neglect?

The study aimed to examine whether modifying the proprioceptive feedback usually associated with a specific movement would decrease the dominance of visual feedback and/or decrease, which appears to be the neglect of proprioceptive feedback in ensuring the accuracy of goal-directed movements. We used a leg positioning recall task and measured the recall error after 15 and 165 acquisition trials performed with both vision and proprioception or proprioception only, under either a normal or a modified proprioception condition (i.e., with a 1-kg load attached to the participants' ankle). Participant learning was evaluated in transfer with proprioception only. In support of the specificity of practice hypothesis, the recall errors in acquisition were significantly smaller when practice occurred with both vision and proprioception, in either the loaded or the unloaded leg condition, and they increased significantly in transfer when vision was withdrawn. An important finding of the study highlighted that withdrawing vision after 165 acquisition trials had less deleterious effects on the recall errors when practice occurred under the loaded leg condition. Under that modified condition, recall errors in transfer were similar when practice occurred with and without vision, whereas larger errors were observed following practice with vision under the normal proprioceptive condition. Overall, these results highlighted the dominance of vision in ensuring accurate leg positioning recall and revealed that the dominance of vision is such that the processing of proprioceptive feedback may be neglected. Importantly, modifying the proprioceptive feedback has the advantage of reducing what appears to be the neglect of proprioceptive information when movement execution occurs in a visuo-proprioceptive context. Practical considerations for rehabilitation are discussed at the end of the manuscript.

Selective visual scaling of time-scale processes facilitates broadband learning of isometric force frequency tracking

The experiment investigated the effect of selectively augmenting faster time scales of visual feedback information on the learning and transfer of continuous isometric force tracking tasks to test the generality of the self-organization of 1/f properties of force output. Three experimental groups tracked an irregular target pattern either under a standard fixed gain condition or with selectively enhancement in the visual feedback display of intermediate (4-8 Hz) or high (8-12 Hz) frequency components of the force output. All groups reduced tracking error over practice, with the error lowest in the intermediate scaling condition followed by the high scaling and fixed gain conditions, respectively. Selective visual scaling induced persistent changes across the frequency spectrum, with the strongest effect in the intermediate scaling condition and positive transfer to novel feedback displays. The findings reveal an interdependence of the timescales in the learning and transfer of isometric force output frequency structures consistent with 1/f process models of the time scales of motor output variability.

Practice with anxiety improves performance, but only when anxious: evidence for the specificity of practice hypothesis

We investigated for the first time whether the principles of specificity could be extended to the psychological construct of anxiety and whether any benefits of practicing with anxiety are dependent on the amount of exposure and timing of that exposure in relation to where in learning the exposure occurs. In Experiment 1, novices practiced a discrete golf-putting task in one of four groups: all practice trials under anxiety (anxiety), non-anxiety (control), or a combination of these two (i.e., the first half of practice under anxiety before changing to non-anxiety conditions, anxiety-control, or the reverse of this, control-anxiety). Following acquisition, all groups were transferred to an anxiety condition. Results revealed a significant acquisition-to-transfer decrement in performance between acquisition and transfer for the control group only. In Experiment 2, novices practiced a complex rock climbing task in one of the four groups detailed above, before being transferred to both a high-anxiety condition and a low-anxiety condition (the ordering of these was counterbalanced across participants). Performance in anxiety transfer was greater following practice with anxiety compared to practice without anxiety. However, these benefits were influenced by the timing of anxiety exposure since performance was greatest when exposure to anxiety occurred in the latter half of acquisition. In the low-anxiety transfer test, performance was lowest for those who had practiced with anxiety only, thus providing support for the specificity of practice hypothesis. Results demonstrate that the specificity of learning principle can be extended to include the psychological construct of anxiety. Furthermore, the specificity advantage appears dependent on its timing in the learning process.

Effect of narrowing the base of support on the gait, gaze and quiet eye of elite ballet dancers and controls

We determined the gaze and stepping behaviours of elite ballet dancers and controls as they walked normally and along progressively narrower 3-m lines (l0.0, 2.5 cm). The ballet dancers delayed the first step and then stepped more quickly through the approach area and onto the lines, which they exited more slowly than the controls, which stepped immediately but then slowed their gait to navigate the line, which they exited faster. Contrary to predictions, the ballet group did not step more precisely, perhaps due to the unique anatomical requirements of ballet dance and/or due to releasing the degrees of freedom under their feet as they fixated ahead more than the controls. The ballet group used significantly fewer fixations of longer duration, and their final quiet eye (QE) duration prior to stepping on the line was significantly longer (2,353.39 ms) than the controls (1,327.64 ms). The control group favoured a proximal gaze strategy allocating 73.33% of their QE fixations to the line/off the line and 26.66% to the exit/visual straight ahead (VSA), while the ballet group favoured a 'look-ahead' strategy allocating 55.49% of their QE fixations to the exit/VSA and 44.51% on the line/off the line. The results are discussed in the light of the development of expertise and the enhanced role of fixations and visual attention when more tasks become more constrained.

Effects of an intensive, task-specific rehabilitation program for individuals with chronic stroke: a case series

PURPOSE

The purpose of this case series was to determine feasibility and evaluate changes in activity and participation outcomes in persons with chronic stroke after an intensive, task-specific rehabilitation program incorporating whole-body and client-centred interventions.

METHOD

Participants with chronic stroke (N = 12) who were ambulatory and had at least minimal arm/hand function were recruited. The program included whole-body goal-focused activities, gait training and strengthening exercises for 4 h, 5 days per week for 2 weeks. Daily educational sessions and a home activities program were also included. Activity-based measures including the Wolf motor function test, Berg balance scale, timed up and go test and 6-min walk test and participation-based measures including the Stroke Impact Scale and Canadian Occupational Performance Measure were collected at pre-test, immediate post-test and 5-month retention.

RESULTS

The effect of the intervention on participation-based outcomes was much greater than on the activity-based outcomes. Minimal detectable differences in self-perceived participation were reported for most participants.

CONCLUSIONS

The intensive, task-specific intervention was a feasible program for these participants with stroke. Although minimal changes in activity-based outcomes were found, the participants perceived improvements in participation with personal goal-related activities that resulted in large effect sizes that were maintained for 5-months after the intervention.

Specificity and variability of practice, and contextual interference in acquisition and transfer of an underhand volleyball serve

The present study investigated the effects of practice composition on acquisition and transfer of the underhand volleyball serve in a standard high school physical education setting. 72 middle-school students (M age = 14.1 yr., SD = 0.7) were selected and assigned to six groups: five experimental (Random, Serial, Blocked, Constant, Specific), and one Control group all pretested. The five experimental groups received 45 acquisition trials over three class periods. Directional quantitative knowledge of results was provided to the students after each trial. After a 72-hr. retention interval, all groups performed 15 underhand volleyball serves without knowledge of results. Analyses indicated (a) better acquisition in the Specific and Constant groups relative to the Serial, Random, and Blocked groups, and (b) significantly superior transfer performance in the Specific and Random groups relative to the Serial, Blocked, Constant, and Control groups. This provides partial support for specificity of learning and contextual interference hypotheses. Practice in accord with the contextual interference hypothesis permits differentiations among varied practice schedules only during transfer.

The amount of practice really matters: specificity of practice may be valid only after sufficient practice

Studies investigating the specificity hypothesis have not always demonstrated that reliance on a specific source offeedback increases with practice. The goal of the present study was to address this inconsistency by having participants practice a throwing task with or without vision at incremental levels (10, 50, 100, or 200 acquisition trials). Following acquisition, all participants in the present experiment performed 10 trials in a no-vision transfer condition. Our results demonstrated that, given a sufficient number of acquisition trials, feedback reliance increased as a function of time engaged in practice. Our results also suggest that increased reliance on a specific source of feedback occurs only after the control strategy for a task is optimized.

On No-KR tests in motor learning, retention and transfer

In this paper we examine the role of no-knowledge of results (KR) tests in motor learning, retention and transfer. A distinction is drawn between studies of KR and studies of other issues in motor learning that use a No-KR test. Arguments are presented against the currently received position that a No-KR test is an essential protocol to examine motor learning, although a No-KR test is most relevant in the few contexts where the outcome information is not naturally available. Perspectives are provided on the limited though proper role of No-KR tests in motor learning, retention and transfer and these are illustrated through experimental examples. It is proposed that the current restrictive interpretation of KR as only augmented outcome information is narrowing not only the context of KR research but also the study of motor learning in general.

The contribution of peripheral and central vision in the control of movement amplitude

Past research has revealed that central vision is more important than peripheral vision in controlling the amplitude of target-directed aiming movements. However, the extent to which central vision contributes to movement planning versus online control is unclear. Since participants usually fixate the target very early in the limb trajectory, the limb enters the central visual field during the late stages of movement. Hence, there may be insufficient time for central vision to be processed online to correct errors during movement execution. Instead, information from central vision may be processed offline and utilised as a form of knowledge of results, enhancing the programming of subsequent trials. In the present research, variability in limb trajectories was analysed to determine the extent to which peripheral and central vision is used to detect and correct errors during movement execution. Participants performed manual aiming movements of 450 ms under four different visual conditions: full vision, peripheral vision, central vision, no vision. The results revealed that participants utilised visual information from both the central and peripheral visual fields to adjust limb trajectories during movement execution. However, visual information from the central visual field was used more effectively to correct errors online compared to visual information from the peripheral visual field.

Especial skills: their emergence with massive amounts of practice

Differing viewpoints concerning the specificity and generality of motor skill representations in memory were compared by contrasting versions of a skill having either extensive or minimal specific practice. In Experiments 1 and 2, skilled basketball players more accurately performed set shots at the foul line than would be predicted on the basis of the performance at the nearby locations, suggesting considerable specificity at this distance. This effect was replicated even when the lines on the court were obscured (in Experiment 2). However, the effect was absent when jump shots were executed in Experiment 3. The authors argue that massive levels of practice at 1 particular member of a class of actions produce specific effects that allow this skill to stand out from the other members of the class, giving it the status of an especial skill. Various theoretical views are proposed to account for the development of these skills.

Effects of specific versus variable practice on the retention and transfer of a continuous motor skill

The effects of specific versus variable practice on retention and transfer was investigated. 30 participants were randomly assigned to one of three practice conditions. The variable speed group practiced on a pursuit rotor task at three different speeds (60, 45, 30 rpm) which were randomly distributed but equal in number for 30 10-sec. trials on Day 1. The Specific Practice group performed all 30 10-sec. trials at 45 rpm on Day 1. On Day 2, all groups performed 15 trials at the 45-rpm retention speed and 15 trials at the 75-rpm transfer speed. The Control group only performed on Day 2. Analysis showed the Specific Practice group had significantly higher scores on Day 1. On Day 2, the Specific Practice group had significantly higher retention scores and the Variable Practice group had higher transfer scores. Continuous motor skills might be practiced differently depending on the environmental context in which the skill may be used.

The Role of Oculomotor Information in the Learning of Sequential Aiming Movements

With their eyes initially on either the home, midline, or final end position, 30 participants practiced a 2-target aiming movement. After 120 acquisition trials, participants performed a retention test and were then transferred to each of the other 2 eye conditions. During acquisition, all groups improved over practice, but the home group showed the greatest improvement. The temporal improvement was most pronounced in the times spent after peak velocity. Retention and transfer tests indicated that participants performed best under eye-movement conditions that were the same as the 1 they had practiced in. There was also positive transfer of training between conditions in which the oculomotor information was similar. Thus, to optimize learning, one should practice under the same afferent and oculomotor conditions that will be required for the final performance.

Age-related differences in vision and proprioception in a lower limb interceptive task: the effects of skill level and practice

This study examined age-related differences in the role of visual proprioception during a lower limb interceptive action and how this varies as a function of skill and practice. In Experiment 1, skilled and less-skilled 8-, 10-, and 12-year-old boys controlled a soccer ball using their preferred foot under full vision and when sight of the effector was occluded. With the exception of the high-skilled 12-year-olds and low-skilled 8-year-olds, participants showed a decrement in peformance when denied access to visual proprioception. In Experiment 2, the effect of practicing under different informational constraints was examined for 12 year-old boys. Children performed varying amounts of practice under full vision, or in a condition where sight of the foot was occluded, before being transferred to the alternative viewing condition. Participants who practiced under occluded viewing conditions showed greater relative improvement in performance over practice and transfer sessions compared with a full vision control group. Some support is provided for the manipulation of visual informational constraints as an effective pedagogical approach to motor learning.

Influence of vision on head stabilization strategies in older adults during walking

BACKGROUND

Maintaining balance during dynamic activities is essential for preventing falls in older adults. Head stabilization contributes to dynamic balance, especially during the functional task of walking. Head stability and the role of vision in this process have not been studied during walking in older adults.

METHODS

Seventeen older adults (76.2 +/- 6.9 years) and 20 young adults (26.0 +/- 3.4 years) walked with their eyes open (EO), with their eyes closed (EC), and with fixed gaze (FG). Participants performed three trials of each condition. Sagittal plane head and trunk angular velocities in space were obtained using an infrared camera system with passive reflective markers. Frequency analyses of head-on-trunk with respect to trunk gains and phases were examined for head-trunk movement strategies used for head stability. Average walking velocity, cadence, and peak head velocity were calculated for each condition.

RESULTS

Differences between age groups demonstrated that older adults decreased walking velocity in EO (p =.022). FG (p = .021), and EC (p = .022). and decreased cadence during EC (p = .007). Peak head velocity also decreased across conditions (p < .0001) for older adults. Movement patterns demonstrated increased head stability during EO. diminished head stability with EC, and improved head stability with FG as older adult patterns resembled those of young adults.

CONCLUSIONS

Increased stability of the lower extremity outcome measures for older adults was indicated by reductions in walking velocity and cadence. Concomitant increases in head stability were related to visual tasks. Increased stability may serve as a protective mechanism to prevent falls. Further, vision facilitates the head stabilization process for older adults to compensate for age-related decrements in other sensory systems subserving dynamic balance.

Examining the specificity of practice hypothesis: is learning modality specific?

The specificity of practice hypothesis was examined using a tracking task. In Experiment 1, visual or auditory feedback about performance was provided. Vision was more useful than audition early in acquisition. Performance gains found in acquisition were maintained during retention, but learning was specific only if the acquisition modality was visual. Specificity did not increase with the amount of practice. In Experiment 2, visual and auditory information were combined. Again, the specificity of practice hypothesis was supported. Also, instructing participants to attend to one information source allowed us to demonstrate that information can be explicitly or implicitly processed. Further, specificity effects may occur because of different rates of development for error detection and correction processes.

Socio-affective characteristics and properties of extrinsic feedback in physiotherapy

BACKGROUND AND PURPOSE

The usual approach in physiotherapy is to communicate the desired action by means of some combination of verbal instruction and explanation, visual demonstration and manual assistance. Patients' and physiotherapists' communication and acts express socio-affective elements which influence the atmosphere governing this interaction. The purpose of this study was to investigate the socio-affective characteristics of the verbal, visual and manual feedback given to their patients by physiotherapists in the performance of their duties.

METHOD

Data were collected by videotaping patient-physiotherapist interaction. Systematic observation was used to depict physiotherapists' and patients' verbal and physical communications. The observation instrument consisted of the categories of verbal communication, physical activities and the socio-affective features of communication.

RESULTS

The physiotherapists used verbal and physical guidance more and visual guidance less. In the main, the properties of the feedback given were motivational and reinforcing. Information feedback appeared very seldom. Verbal cues were mostly short comments. The main significance of manual cueing was in the tactile input that was used in orienting patients to produce the correct movement. The most effective way of helping patients to understand the purpose of the action and the sequential organization of the subroutine of the movement was to give a demonstration containing the relevant visual and verbal cues.

CONCLUSIONS

The extensive use of verbal and manual guidance found in this study needs to be thought over carefully, especially as physiotherapists seemed to use these techniques more as routine than as a result of careful consideration. The socio-affective atmosphere seems to influence physiotherapists' ways of giving feedback to their patients. Further research is needed to determine the most effective way of arranging guidance strategies for physiotherapists to produce effective feedback.

The effect of practice on component submovements is dependent on the availability of visual feedback

Participants (N = 16) were given extensive practice (1,500 trials) on a perceptual-motor aiming task. The full-vision (FV) group practiced with vision of their response cursor, whereas the no-vision (NV) group practiced in a condition without vision. Movements were made as quickly and accurately as possible, and knowledge of results (KR) was provided. The authors tested the importance of vision early and late in practice by transferring participants to the NV condition without KR. The effects of practice differed between the two conditions. The FV group increased the speed of initial impulse to get to the target quickly, then relied on vision to make discrete error corrections. Transfer tests revealed that reliance on vision remained after extensive practice. For the NV group, practice effects were associated with a reduction in the extent to which discrete error corrections were produced.

Manipulating visual informational constraints during practice enhances the acquisition of catching skill in children

Previous motor learning studies examining the effects of practicing to catch one-handed under varying informational constraints on subsequent skill acquisition are equivocal, perhaps due to the use of relatively inexperienced adult participants. Ecological theory predicts that directing the learner's search for information in the perceptual-motor workspace can enhance skill acquisition. This study manipulated visual informational constraints on novice children (ages 9-10 years) learning to catch one-handed. A crossover transfer design was implemented in which one group acted as controls while two other groups practiced either without visual restrictions before transferring to full vision, or vice versa. The data indicated that learners forced to seek additional information sources under restricted viewing conditions demonstrated a greater positive, accumulative residual effect on acquiring a catching skill. The findings contradict current work on the specificity of practice hypothesis and suggest that varying visual informational constraints to encourage exploratory practice may represent a significant pedagogical approach to motor learning in sport.