Affordance-based control of braking in cycling: Experience reveals differences in the style of control

We investigated whether in an in-situ collision avoidance experiment cyclists regulate braking by adopting an affordance-based control strategy. Within an affordance-based control strategy for braking, deceleration is controlled relative to the maximum achievable deceleration rather than by nulling out deviations from ideal deceleration, and potentially allowing for different braking styles. Twenty active- and eighteen inactive-cyclists were asked to cycle on a straight path in an indoor gym and to stop as close as possible in front of a stationary obstacle. Maximum achievable deceleration was manipulated by loading the bike: no-load, load-5 kg, and load-10 kg. Two approach distances were used to vary cycling speed. Participants in both groups stopped farther from the obstacle when approaching with long- than short-initial distance conditions. No systematic effects of loading on braking performance and control were found across the two groups. However, both groups did increase the magnitude of brake adjustments as ideal deceleration increased and got closer to the action boundary, even when current deceleration approached the ideal deceleration. This indicates that participants adopted an affordance-based control strategy for braking. Two braking styles were identified: an aggressive style, characterized by a late braking onset and a high, steep peak in ideal deceleration, and a conservative style, characterized by an early braking onset and gradual, linear increase in ideal deceleration. The aggressive braking style was more prevalent among the active-cyclists. We suggest that the braking styles emerge from differences in calibration between information and action. The novelty of our work lies in confirming that cyclists adopt an affordance-based control strategy in an in-situ experiment and in demonstrating and explicating how affordance-based control can incorporate the emergence of different styles of braking.

No evidence that visual exploratory activity distinguishes the super elite from elite football players

Visual exploratory activities (VEA) refer to head and body movements that football players make prior to receiving the ball to search possibilities for action. VEA is considered a key performance indicator that differentiates the skill level of players. This study revisited whether VEA also distinguishes super elite, award winning players from their elite teammates without awards. To this end, video footage from the men's UEFA Champions League season 2018-2019 featuring the super elite players (n = 18) and the elite players (n = 18) was analyzed. To reduce the potential differences in match dynamics as much as possible, the selected players in the two groups were of the same team, playing the same match, in the same positioning line. VEA (i.e. frequency per unit time) during the penultimate and final pass prior to ball reception and performance (i.e. percentages of adequate ball contacts and subsequent actions) were compared between the two groups of players using ANOVA and Mann-Whitney tests, respectively. In addition, hierarchical stepwise regression analyses were conducted to explore the degree to which VEA was predicted by group and subsequent performance. The results showed that the players had higher VEA during the final pass (M = 0.45) than the penultimate pass (M = 0.41). There were no significant differences in VEA or performance between the two groups. Also, the regression analyses did not deliver significant models. We conclude that with partial control for match dynamics, no evidence emerged to support that VEA distinguishes super elite players from elite football players.

Self-Controlled Video Feedback Facilitates the Learning of Tactical Skills in Tennis

Purpose: This study aimed to examine the effect of self-controlled video feedback on the learning of tactical motor skills in tennis, and additionally, whether this was affected by learners' self-efficacy and self-regulative skills. Method: Twenty-three intermediately skilled tennis players were assigned to either a self-controlled group that was provided video feedback on request or a yoked group that received an identical, externally controlled video feedback schedule. In three training sessions participants practiced serve and volley play. Video feedback with attentional cueing and transitional statements that focused solely on individual tactical gameplay was provided by a licensed tennis coach. Individual tactical performance was measured with a custom designed Tactical Tennis Tool (TTT) in a pretest, posttest and in a one-week retention test. Before each test self-efficacy was measured, and a questionnaire was administered to measure self-regulative skills. Results: Analyses revealed significantly larger improvements in tactical performance relative to the pretest for the self-controlled group than for the yoked group in both the posttest and the one-week retention test. No differences were found in self-efficacy. Finally, the improvements in tactical performance were not predicted by self-efficacy and/or self-regulative skills. Conclusion: The advantage of self-controlled video feedback extends to the learning of a complex tactical task in tennis. Future research should verify the observed benefits of a self-controlled learning environment in comparison to a coach-controlled learning environment.

An investigation into the effect of audiences on the soccer penalty kick

The effects of audiences in boosting the performance of the home team (i.e. home advantage) in sports like soccer have been studied extensively. However, much less attention has been paid to how audiences influence the performance of individual team members. To this end, the current study compared in-game penalty kicks taken by home and away teams in eight major European leagues with audiences in the 2018-2019 season to kicks taken without audiences in the 2020-2021 season during the COVID-19 pandemic. No unequivocal evidence for home or away team advantage with respect to penalty outcome (i.e. goal, no goal) was revealed. Yet, results did show that the number of missed penalties of home teams (i.e. penalties kicked at or outside the frame of the goal) significantly reduced when no audience was present. This supports the hypothesis that home audiences increase anxiety of penalty takers and thus the likelihood of choking. However, the reduced number of missed penalties did not significantly increase penalty outcome of home teams when playing without audiences, suggesting additional, unidentified effects of audiences, possibly also including opponent goalkeepers. Finally, when no audience was present, away teams demonstrated significantly poorer penalty outcome. Future research investigating the effects of audiences on the penalty kick should consider more detailed performance measures of both penalty takers and goalkeepers.

Examining the effect of task constraints on the emergence of creative action in young elite football players by using a method combining expert judgement and frequency count

In adult football, small-sided games are associated with increased action variability and suggested to promote more creative actions compared to regular 11v11 formats. This aligns with predictions from an ecological approach to perception and action that creative actions emerge in environments that grant variability in action, instead of being an expression of the individual player's ability to generate ideas. To further evidence for this prediction, the current study aimed to expand this observation to elite youth football players. To this end, the number of different and creative actions in 4v4 small-sided game and a 11v11 regular-sided game among 10- to 12-year-old elite football players were examined. We analyzed a total of 7922 actions, which were categorized for type and creativity. Based on a subset of these actions, a panel of elite football coaches judged action types occurring below 0.5% as significantly more creative than more frequent action types. Hence, we used an occurrence of 0.5% as threshold to distinguish creative actions from non-creative actions. The results showed that the total number of actions, the number of different action types, the number creative actions and the number of different creative action types was significantly higher for the small-sided game format than the regular-sided game. In conclusion, this study confirms that in elite youth football, small-sided games induce a more variable and creative action repertoire. This shows that practitioners can design learning environments that promote the emergence of creative actions.

How intrinsically motivating are swimming instructors/lessons in the Netherlands? An observational study through the lens of self-determination theory

Background

It is desirable that (more) children continue swimming after having completed their swimming lessons to preserve their swimming skills and water safety, and as part of an active, healthy lifestyle. This may be encouraged by stirring children's intrinsic motivation for swimming during swimming lessons. However, it is currently unknown how intrinsically motivating swimming lessons are in Western countries.

Purpose

This study examined to what extent swimming instructors in the Netherlands cater to the basic needs of autonomy, competence, and relatedness, which, according to Self-Determination Theory (SDT), promote intrinsic motivation. Additionally, it examined whether an SDT-based teaching program prompts instructors to better meet these needs, and to what extent the teaching program, the education and experience of the instructor, and the group size predict the employment of SDT in swimming lessons.

Methods

A total of 128 swimming lessons given by equally many instructors were observed in the Netherlands and rated on a modified version of the SDT teaching style scale to assess autonomy, competence, and relatedness support. The swimming lessons referred to four teaching programs, one of which was explicitly based on SDT.

Results

Instructors exhibited autonomy-thwarting, weakly competence-supportive, and relatedness-supportive behaviors. The SDT-based teaching program scored higher on the provision of autonomy, competence, and relatedness in lessons. This finding was significant for autonomy. Teaching program was the only significant predictor of SDT employment by instructors.

Conclusion

Further improvement is desirable in catering to the basic needs, particularly autonomy, which can be achieved by deliberately implementing the principles of SDT into teaching programs for swimming.

The effectiveness of penalty takers' deception: A scoping review

Attackers are supposed to take advantage of producing deceptive actions in competitive ball sports, particularly in penalty situations. We conducted a scoping review of the experimental literature to scrutinize whether penalty takers do indeed benefit from using deceptive actions in penalty situations, especially by increasing the likelihood to score a goal. Studies using video-based and in-situ tasks in which soccer and handball goalkeepers try to save a penalty were evaluated. Results showed that penalty takers' manipulation of spatial information available to the goalkeeper during deception (i.e., by using misleading and/or disguising actions) is less effective in in-situ than video-based studies. We argue that this difference occurs because goalkeepers adapt differently to the spatiotemporal constraints in the video-based and in-situ tasks. Goalkeepers appear to prioritize picking up spatial information in video-based tasks while prioritizing temporal information in-situ tasks. Therefore, the manipulation of spatial information appears to be less effective in the more representative in-situ studies than in video-based studies. In order to deceive, penalty takers are advised to manipulate temporal information during on-field penalty situations.

Mastering balance: The use of balance bicycles promotes the development of independent cycling

Children who learn to cycle at a young age do this by using training bicycles that simplify control requirements compared with regular bicycles, such as bicycles with training wheels or balance bikes without pedals. The primary purpose of the current study was to investigate whether the two types of training bicycles result in a different age of onset of independent cycling on a regular bicycle. We asked parents of 4‐ to 6‐year‐old children (n = 173) to complete a questionnaire regarding their child's bicycling history. The results showed that children who had practised with a balance bicycle started practising at a younger age, had shorter practice duration, and were able to cycle independently at a younger age in comparison to children who had practised with a bicycle with training wheels (or with both training bicycles). We argue that the observed advantage of balance bicycle is associated with the balance bicycle actively challenging postural control. Further research is needed to uncover the impact of training bicycles on the further development of the foundational skill of cycling.

How wide should you view to fight? Establishing the size of the visual field necessary for grip fighting in judo

Peripheral vision is often considered vital in (combat) sports, yet most experimental paradigms (e.g., eye tracking) ignore peripheral information or struggle to make inferences about the role of peripheral vision in an in-situ performance environment. This study aimed to determine where visual information is located in the peripheral field during an in-situ combat sports task. Eight advanced judokas competed in grip-fighting exchanges while wearing a mobile eye-tracker to locate gaze direction. Three-dimensional position data of the head and hands were tracked using a VICON motion capture system. Gaze analysis through automatic feature detection showed that participants predominantly fixated on their opponent's chest. Kinematic data were used to calculate the angles between the opponent's hands and the gaze-anchor point on the chest of the opponent. Results revealed a nonlinear relationship between visual field (VF) size and visibility of the hands, with athletes needing a VF of at least 30-40 degrees radius to simultaneously monitor both hands of the opponent most of the time. These findings hold implications for the regulation of Paralympic judo for athletes with vision impairment, suggesting that a less severe degree of impairment should be required to qualify than the current criterion of 20 degrees radius.

Motor learning methods that induce high practice variability reduce kinematic and kinetic risk factors of non-contact ACL injury

The prevention of non-contact anterior cruciate ligament (ACL) injuries often involves movement training, but the effectiveness of different motor learning methods has not been fully investigated. The purpose of this study was therefore to examine the effects of linear pedagogy (LP), nonlinear pedagogy (NLP) and differential learning (DL) motor learning methods on changing kinetic and kinematic factors during expected sidestep cutting related to non-contact ACL injuries. These methods primarily differ in the amount and type of movement variability they induce during practice. Sixty-six beginner male soccer players (27.5 ± 2.7 years, 180.6 ± 4.9 cm, 78.2 ± 4.6 kg) were randomly allocated to a group that trained for 12 weeks with either a LP, NLP or DL type of motor learning methods. All participants completed a biomechanical evaluation of side-step cutting before and after the training period. Analysis of covariance was used to compare post-testing outcomes among the groups while accounting for group differences in baseline performance. Changes in all kinematic and kinetic variables in NLP and DL groups were significantly higher compared to the LP group. Most comparisons were also different between NLP and DL group with the exception of vertical ground reaction force, the knee extension/flexion, knee valgus, and ankle dorsiflexion moments. Our findings indicate that beginner male soccer players may benefit from training programs incorporating NLP or DL versus LP to lower biomechanical factors associated with non-contact ACL injury, most likely because of the associated increased execution variability during training. We discuss that practitioners should consider using the NLP or DL methods, and particular the NLP, during which variability is induced to guide search, when implementing training programs to prevent ACL injuries in soccer.

Using Modified Equipment in Field Hockey Leads to Positive Transfer of Learning Effect

Cross-education is the phenomenon in which repeated practice of a unilateral motor task does not only result in performance improvement of the trained limb, but also in the untrained contralateral limb. The aim of this study was to test whether cross-education or positive transfer of learning is also achieved for tasks in which both limbs contribute in different ways by using modified equipment that switches the limbs' role. To this end, a reverse field hockey stick was used that requires a mirroring of arm and hand use and dominance (i.e., right hand on top of the hockey stick instead of the left hand). Two groups of young skilled female field hockey players participated in a crossover-design, in which participants received four training sessions with a reverse hockey stick followed by four training sessions with a regular hockey stick, or vice versa. In a pre-test, intermediate test (following the first intervention period), a post-test (after the second intervention period) and a retention test, participants' performance on a field hockey skill test with a regular hockey stick was measured. The results revealed that training with the reversed hockey stick led to significantly increased improvements compared to training with a regular hockey stick. We conclude that modified equipment can be used to exploit positive transfer of learning by switching the limbs' roles. The findings are discussed by referring to the symmetry preservation principle in dynamic systems theory and have clear practical relevance for field hockey trainers and players seeking to further improve field hockey skills.

The Interplay of Goalkeepers and Penalty Takers Affects Their Chances of Success

Research in penalty kicking has primarily focused on spatial decision making, while temporal decision making has largely been neglected, even though it is as critical for success. Temporal decision making concerns goalkeepers choosing when to initiate their jump to the ball during the penalty taker's run-up (i.e., jump early or wait long), and penalty takers deciding where to kick the ball, either prior to the run-up or after the goalkeeper has committed to one side. We analyzed penalty takers' and goalkeepers' behavior during penalty shoot-outs at FIFA World Cups and UEFA European Championships to scrutinize if temporal aspects of decision making have an impact on penalty kick success. Results indicate that the likelihood of a penalty kick being scored depends on the combination of penalty takers' and goalkeepers' temporal decision-making strategies. Hence, moving early more often seems fruitful for goalkeepers, while penalty takers should consider varying penalty kick strategy between attempts.

The influence of locative expressions on context-dependency of endpoint control in aiming

It has been claimed that increased reliance on context, or allocentric information, develops when aiming movements are more consciously monitored and/or controlled. Since verbalizing target features requires strong conscious monitoring, we expected an increased reliance on allocentric information when verbalizing a target label (i.e. target number) during movement execution. We examined swiping actions towards a global array of targets embedded in different local array configurations on a tablet under no-verbalization and verbalization conditions. The global and local array configurations allowed separation of contextual-effects from any possible numerical magnitude biases triggered from calling out specific target numbers.The patterns of constant errors in the target directionwere used to assess differences between conditions. Variation in the target context configuration systematically biased movement endpoints in both the no-verbalization and verbalization conditions. Ultimately, our results do not support the assertion that calling out target numbers during movement execution increases the context-dependency of targeted actions.

Action capability constrains visuo-motor complexity during planning and performance in on-sight climbing

The capability to adapt to changing conditions is crucial for safe and successful performance in physical activities and sports. According to the affordance‐based control perspective, individuals act in such a way as to take into account the limits of their capability to act. However, it is not clear how strength interacts with skill in shaping performer‐environment interactions. We, therefore, determined whether fingertip strength influences patterns of gaze and climbing behavior on new routes of ever‐increasing difficulty. We expected that comparatively weaker climbers would show less complex behavior because of an inability to perceive and act. Stronger climbers would show more complex visuo‐motor behavior because more opportunities for action remain, even as route difficulty increases. For very strong climbers the route would not be challenging enough, and less complex patterns suffice. Twenty climbers, ranging from lower grade to elite level participated. Maximum fingertip strength was obtained. Participants previewed and then climbed two separate 3 m long traverses, gradually decreasing in edge depth. Gaze and hip positions were collected for subsequent computation of gaze transition entropy (during preview) and hip displacement entropy (during climbing). Data revealed statistically significant curvilinear relationships between both fingertip strength and gaze transition entropy, and fingertip strength, and hip displacement entropy. Visuo‐motor complexity is scaled by how close the individual must act relative to boundaries of what the environment affords and does not afford for action given the individual constraints. Future research should examine in greater detail relationships between action capabilities and functional movement variability.

Combat as an Interpersonal Synergy: An Ecological Dynamics Approach to Combat Sports

In combat sports, athletes continuously co-adapt their behavior to that of the opponent. We consider this interactive aspect of combat to be at the heart of skilled performance, yet combat sports research often neglects or limits interaction between combatants. To promote a more interactive approach, the aim of this paper is to understand combat sports from the combined perspective of ecological psychology and dynamic systems. Accordingly, combat athletes are driven by perception of affordances to attack and defend. Two combatants in a fight self-organize into one interpersonal synergy, where the perceptions and actions of both athletes are coupled. To be successful in combat, performers need to manipulate and take advantage of the (in)stability of the system. Skilled performance in combat sports therefore requires brinkmanship: combatants need to be aware of their action boundaries and purposefully act in meta-stable regions on the limits of their capabilities. We review the experimental literature to provide initial support for a synergetic approach to combat sports. Expert combatants seem able to accurately perceive action boundaries for themselves and their opponent. Local-level behavior of individual combatants has been found to lead to spatiotemporal synchronization at the global level of a fight. Yet, a formal understanding of combat as a dynamic system starting with the identification of order and control parameters is still lacking. We conclude that the ecological dynamics perspective offers a promising approach to further our understanding of skilled performance in combat sports, as well as to assist coaches and athletes to promote optimal training and learning.

Persistent handwriting problems are hard to predict: A longitudinal study of the development of handwriting in primary school

BACKGROUND

After one year of tuition, up to a third of primary school children show insufficient handwriting. It is unclear whether this early insufficient handwriting predicts persistent handwriting problems, because there is a dearth of studies that followed developmental trajectories longitudinally.

AIMS

To describe handwriting development in primary school children longitudinally and to determine predictive positive value and sensitivity of early handwriting assessment. To analyse whether underlying abilities helps early identification of persistent handwriting problems.

METHODS

173 primary school children were yearly assessed for four years using the Concise Assessment Scale for Children's Handwriting and the Beery Buktenica developmental test of visual-motor integration.

RESULTS

Both quality and speed of handwriting increased with years of tuition, with a pronounced increase in quality between two and three years of writing tuition. Sensitivity and positive predictive value were low. The only significant predictor of handwriting quality was handwriting quality in the previous year. For handwriting speed, no significant developmental model was revealed.

CONCLUSIONS

Quality and speed of handwriting after one year of tuition is not sufficiently predictive for distinguishing between transient insufficient handwriting and persistent handwriting problems three years later. Practitioners should hold back when referring children for remedial teaching.

Moving Advertisements Systematically Affect Gaze Behavior and Performance in the Soccer Penalty Kick

The aim of the current study was to investigate whether a moving advertisement positioned behind the goal area would influence the visual attention of participants performing a soccer penalty kick, and, whether this would an effect on subsequent motor performance. It was hypothesized that if the (moving) advertisement would function as a distractor, then this would result in non-specific disruptions in penalty performance measures, especially affecting aiming location and precision. Alternatively, it was reasoned that, in line with the Dunker illusion, the moving advertisement would systematically affect perception of target location, resulting in changes in penalty performance and aiming that are specific for the direction of motion of the advertisement. To test these hypotheses, we investigated the gaze behavior and kicking performance of intermediate skilled soccer players taking penalty kicks in three differing advertisement conditions, namely no advertisement, a stationary advertisement, and a moving advertisement. The latter condition consisted of an advertisement moving from left to right and an advertisement moving from right to left. Results showed that a moving advertisement placed behind the goal area indeed caught the visual attention of soccer penalty kickers using a goalkeeper-dependent kicking strategy. Participants kicking performance tended to be less variable within the no advertisement condition compared to the moving advertisement condition. In addition, systematic, direction-specific effects on aiming were found when comparing conditions in which the advertisement moved in opposite directions. This pattern of findings indicate that the accuracy of the penalty kick is impacted by task-irrelevant contextual information.

On the Education About/of Radical Embodied Cognition

In mainstream or strong university education, the teacher selects and transmits knowledge and skills that students are to acquire and reproduce. Many researchers of radical embodied cognitive science still adhere to this way of teaching, even though this prescriptive pedagogy deeply contrasts with the theoretical underpinnings of their science. In this paper, we search for alternative ways of teaching that are more aligned with the central non-prescriptive and non-representational tenets of radical embodied cognitive science. To this end, we discuss recent views on education by Tim Ingold and Gert Biesta, which are based on Dewey's philosophy of pragmatism and Gibsons' ecological approach. The paper starts by introducing radical embodied cognitive science, particularly as it relates to motor skill learning, one of our prime interests in research and teaching. Next, we provide a synopsis and critique of the still dominant prescriptive and explicating pedagogy of strong education. Following Ingold and Biesta, we search for a weak alternative through a careful consideration of the education of attention and the participating teacher. To illustrate our arguments, we use examples of the first author's teaching about/of motor skill learning. The paper is concluded by briefly considering the implications of weak education for a radical embodied science of motor skill learning.

Efficient search under constraints and not working memory resources supports creative action emergence in a convergent motor task

Creative (original and functional) solutions to problems can be facilitated by guiding search behavior. According to cognitive models, when solving convergent tasks (tasks with few solutions), high available working memory (WM) resources and capacity can guide creative solution emergence via repeated (persistent) search within a solution subcategory. However, no clear associations have been found of WM capacity on creative outcomes when tasks require the individual to enact solutions in divergent doing tasks. This study further tested constraints on WM resources on search behavior and creative outcomes in a convergent doing task. Novices to combat sports were asked to repeatedly strike a target with the intent to achieve an individualized target force. In order to manipulate available WM resources, every ten strikes, participants were asked to recall and then retain a sequence of 5 digits (high load group: n = 21) or 2 digits (low load group: n = 21). The task constraints favored the functionality (or appropriateness) of a qualitatively distinct, non-obvious solution. Functionality was assessed using the force registered for each strike. Originality was assessed in terms of how infrequently actions occurred. Finally, search behavior was quantified based on changes in which limb was used and changes in which part of the limb was used from one strike to the next. There were no significant effects of WM load on creativity outcomes, solution search, or task success. Rather, task success was related to efficient search and creativity. Future research should focus on constraints (other than WM resources) that promote efficient search.

Self-Control in Aiming Supports Coping With Psychological Pressure in Soccer Penalty Kicks

This study addressed the question whether coaches better allow athletes to self-control their decisions when under pressure or whether to impose a decision upon them. To this end, an experiment was conducted that manipulated the soccer kickers' degree of control in decision-making. Two groups of elite under-19 soccer players (n = 18) took penalty kicks in a self-controlled (i.e., kickers themselves decided to which side to direct the ball) and an externally controlled condition (i.e., the decision to which side to direct the ball was imposed upon the kickers). One group performed the penalty kick under psychological pressure (i.e., the present coaching staff assessed their performance), while the second group performed without pressure. Just before and after performing the kicks, CSAI-2 was used to measure cognitive and somatic anxiety and self-confidence. Further, the number of goals scored, ball placement and speed, and the duration of preparatory and performatory behaviors were determined. The results verified increased levels of cognitive and somatic anxiety after performing the kicks in the pressured group compared to the no-pressure group. In addition, degree of self-control affected the participants' performance, particularly in the pressured group. They scored more goals and placed the kicks higher in the self-controlled than in the externally-controlled condition. Participants also took more time preparing and performing the run-up in the self-controlled condition. Findings indicate that increased self-control helps coping with the debilitating effects of pressure and can counter performance deteriorations. The findings are discussed within the framework of self-control theories, and recommendations for practitioners and athletes are made.

The differential effects of task difficulty on the perception of passing distance and subsequent passing action in a field hockey push pass task

The aims of the study were to initially investigate whether the perceived distance of a field hockey push pass task was influenced by manipulating task difficulty (Experiment 1), and further, expanding on the research, whether perceptual biases would translate into the execution of a corresponding push pass action (Experiment 2). Based on predictions from the two-visual systems model, we hypothesized that the action-specific perceptual biases in distance perception would not translate into the control of movement. In Experiment 1, elite field hockey players estimated the distance from targets that differed in size before making push pass actions toward the target (i.e., the smaller targets being more difficult). Results showed that participants did estimate the perceived distance of the push pass task to be larger as a function of task difficulty. We found a similar result in Experiment 2, and in addition, manipulated the required outcome of the push-pass while measuring the speed of the push-pass and found that a perceptual bias did not translate into the execution of the actual push pass task (Experiment 2). In line with the action-specific account of perception, a perceptual bias arose that may assist in making adaptive action choices. However, consistent with the two-visual systems model, this perceptual bias did not affect subsequent control of movement, preventing it from becoming maladaptive. Implications for talent identification and development are briefly discussed.

Adverse effects of anxiety on attentional control differ as a function of experience: A simulated driving study

This study tested whether adverse effects of state anxiety on attention and performance may be modulated by experience. Sixteen experienced and eleven inexperienced drivers drove in a simulator under low- and high-stress conditions. Anxiety was manipulated by competition, the presence of an evaluator, external video camera, and traffic noise. Most drivers showed greater anxiety scores and higher mean heart rates following manipulation. In both groups increased state anxiety decreased car speed control and caused more collisions, accompanied by fewer fixations of longer duration towards the driving lane across a horizontally narrower region. Inexperienced drivers increased the number of short fixations towards cars, while experienced drivers increased the number of short fixations on the speedometer. Although anxiety impairs processing efficiency and performance effectiveness for both groups, attentional changes differ as a function of experience. Inexperienced drivers tended to shift attention to threatening stimuli, while experienced drives were more likely to consciously monitor task goal.

Are the effects of internal focus instructions different from external focus instructions given during balance training in stroke patients? A double-blind randomized controlled trial

Objective:

This study aimed to assess if external focus instructions result in greater improvements in motor skill and automaticity compared to internal focus instructions in stroke patients.

Design:

Double-blind randomized controlled trial.

Setting:

Inpatient stroke rehabilitation unit.

Subjects:

A total of 63 stroke patients (Meanage = 59.6 ± 10.7 years; Meandays since stroke = 28.5 ± 16.6; MedianFunctional Ambulation Categories = 4).

Interventions:

Patients were randomly assigned to an internal ( N = 31) or external ( N = 32) focus instruction group. Both groups practiced a balance board stabilization task, three times per week, for three weeks. Balance performance was assessed at baseline, and after one and three weeks of practice.

Main measures:

Primary outcome was the threshold stiffness (Nm/rad) at which patients could stay balanced. Secondary outcomes were patients’ sway (root-mean-square error in degrees) at the baseline threshold stiffness under single- and dual-task conditions, and their performance on the Timed Up and Go Test and Utrecht Scale for Evaluation of Rehabilitation.

Results:

Both groups achieved similar improvements in threshold stiffness (∆= 27.1 ± 21.1 Nm/rad), and single- (∆= 1.8 ± 2.3° root-mean-square error) and dual-task sway (∆= 1.7 ± 2.1° root-mean-square error) after three weeks of practice. No differences were found in improvements in clinical tests of balance and mobility. Patients with comparatively good balance and sensory function, and low attention capacity showed greatest improvements with external focus instructions.

Conclusion:

External focus instructions did not result in greater improvement in balance skill in stroke patients compared to internal focus instructions. Results suggest that tailoring instructions to the individual stroke patient may result in optimal improvements in motor skill.

Implicit learning increases shot accuracy of football players when making strategic decisions during penalty kicking

Implicit learning has been proposed to improve athletes' performance in dual-task situations. Yet, only a few studies tested this with a sports-relevant dual-task. Hence, the current study aimed to compare the effects of implicit and explicit training methods on penalty kicking performance. Twenty skilled football players were divided in two training groups and took part in a practice phase to improve kicking accuracy (i.e., without a goalkeeper) and in a post-test in order to check penalty kick performance (i.e., accuracy including a decision to kick to the side opposite the goalkeeper's dive). Results found that the implicit and explicit training method resulted in similar levels of decision-making, but after implicit training this was achieved with higher kicking accuracy. Additionally, applications for football players and coaches are discussed.

Individual Differences Influencing Immediate Effects of Internal and External Focus Instructions on Children's Motor Performance

PURPOSE

A large pool of evidence supports the beneficial effect of an external focus of attention on motor skill performance in adults. In children, this effect has been studied less and results are inconclusive. Importantly, individual differences are often not taken into account. We investigated the role of working memory, conscious motor control, and task-specific focus preferences on performance with an internal and external focus of attention in children.

METHODS

Twenty-five children practiced a golf putting task in both an internal focus condition and external focus condition. Performance was defined as the average distance toward the hole in 3 blocks of 10 trials. Task-specific focus preference was determined by asking how much effort it took to apply the instruction in each condition. In addition, working memory capacity and conscious motor control were assessed.

RESULTS

Children improved performance in both the internal focus condition and external focus condition (ŋ_p² = .47), with no difference between conditions (ŋ_p² = .01). Task-specific focus preference was the only factor moderately related to the difference between performance with an internal focus and performance with an external focus (r = .56), indicating better performance for the preferred instruction in Block 3.

CONCLUSION

Children can benefit from instruction with both an internal and external focus of attention to improve short-term motor performance. Individual, task-specific focus preference influenced the effect of the instructions, with children performing better with their preferred focus. The results highlight that individual differences are a key factor in the effectiveness in children's motor performance. The precise mechanisms underpinning this effect warrant further research.

Creative Motor Actions As Emerging from Movement Variability

In cognitive science, creative ideas are defined as original and feasible solutions in response to problems. A common proposal is that creative ideas are generated across dedicated cognitive pathways. Only after creative ideas have emerged, they can be enacted to solve the problem. We present an alternative viewpoint, based upon the dynamic systems approach to perception and action, that creative solutions emerge in the act rather than before. Creative actions, thus, are as much a product of individual constraints as they are of the task and environment constraints. Accordingly, we understand creative motor actions as functional movement patterns that are new to the individual and/or group and adapted to satisfy the constraints on the motor problem at hand. We argue that creative motor actions are promoted by practice interventions that promote exploration by manipulating constraints. Exploration enhances variability of functional movement patterns in terms of either coordination or control solutions. At both levels, creative motor actions can emerge from finding new and degenerate adaptive motor solutions. Generally speaking, we anticipate that in most cases, when exposed to variation in constraints, people are not looking for creative motor actions, but discover them while doing an effort to satisfy constraints. For future research, this paper achieves two important aspects: it delineates how adaptive (movement) variability is at the heart of (motor) creativity, and it sets out methodologies toward stimulating adaptive variability.

Examining Developmental Changes in Children's Motor Imagery: A Longitudinal Study

Using a longitudinal design, the present study examined developmental changes in the employment of (motor) imagery strategies on the hand laterality judgment (HLJ) task in children. All children (N = 23) participated three times, at ages of 5, 6, and 7 years. Error percentages and response durations were compared to a priori defined sinusoid models, representing different strategies to judge hand laterality. Response durations of correct and incorrect trials were included. Observed data showed that task performance was affected by motor constraints, both in children who performed accurately at 5 years of age and in the children who did not. This is the first study to show that 5-year-olds—even when not successful at the task—employ motor imagery when engaged in this task. Importantly, although the children became faster and more accurate with age, no developmental changes in the employed motor imagery strategy were observed at ages of 5, 6, and 7 years. We found that 5-year-old children are able to use a motor imagery strategy to perform the HL J task. Although performance on this task improved with age, our analyses showed that the employed strategy to solve this task remained invariant across age.

Conscious Control Is Associated With Freezing of Mechanical Degrees of Freedom During Motor Learning

This study investigated whether conscious control is associated with freezing of mechanical degrees of freedom during motor learning. Participants practiced a throwing task using either error-strewn or error-reduced practice protocols, which encourage high or low levels of conscious control, respectively. After 24 hr, participants engaged in a series of delayed retention and transfer tests. Furthermore, propensity for conscious control was assessed using participants' ratings and freezing was gauged through movement variability of the throwing arm. Performance was defined by mean radial error. In the error-strewn group, propensity for conscious control was positively associated with both freezing and performance. In the error-reduced group, propensity for conscious control was negatively associated with performance, but not with freezing. These results suggest that conscious control is associated with freezing of mechanical degrees of freedom during motor learning.

The Effects of Optical Illusions in Perception and Action in Peripersonal and Extrapersonal Space

While the two visual system hypothesis tells a fairly compelling story about perception and action in peripersonal space (i.e., within arm's reach), its validity for extrapersonal space is very limited and highly controversial. Hence, the present purpose was to assess whether perception and action differences in peripersonal space hold in extrapersonal space and are modulated by the same factors. To this end, the effects of an optic illusion in perception and action in both peripersonal and extrapersonal space were compared in three groups that threw balls toward a target at a distance under different target eccentricity (i.e., with the target fixated and in peripheral field), viewing (i.e., binocular and monocular viewing), and delay conditions (i.e., immediate and delayed action). The illusory bias was smaller in action than in perception in peripersonal space, but this difference was significantly reduced in extrapersonal space, primarily because of a weakening bias in perception. No systematic modulation of target eccentricity, viewing, and delay arose. The findings suggest that the two visual system hypothesis is also valid for extra personal space.

Gaze control during interceptive actions with different spatiotemporal demands

It is widely accepted that the sources of information used to guide interceptive actions depend on conflicting spatiotemporal task demands. However, there is a paucity of evidence that shows how information pick-up during interceptive actions is adapted to such conflicting constraints. The present study therefore examined the effects of systematic manipulations of spatiotemporal constraints on performance, timing and gaze in an in situ interceptive action. To this end, expert futsal goalkeepers faced penalty kicks taken from 10 m and 6 m. With the more lenient spatiotemporal constraints (i.e., kicks from 10 m), the goalkeepers saved more kicks, initiated their actions later, and looked longer toward ball relative to the penalty takers' body. Furthermore, analysis of gaze patterns showed that interindividual variations in information pick-up were related to the unfolding of the penalty taker's action, revealing a less variable, funnel-like gaze pattern toward the end of the action. These findings are interpreted to reflect that changes in spatiotemporal demands induce the differential use of information for the accurate control of interceptive actions. (PsycINFO Database Record

Nothing magical: pantomimed grasping is controlled by the ventral system

In a recent amendment to the two-visual-system model, it has been proposed that actions must result in tactile contact with the goal object for the dorsal system to become engaged (Whitwell et al., Neuropsychologia 55:41–50, 2014). The present study tested this addition by assessing the use of allocentric information in normal and pantomime actions. To this end, magicians, and participants who were inexperienced in performing pantomime actions made normal and pantomime grasps toward objects embedded in the Müller–Lyer illusion. During pantomime grasping, a grasp was made next to an object that was in full view (i.e., a displaced pantomime grasping task). The results showed that pantomime grasps took longer, were slower, and had smaller hand apertures than normal grasping. Most importantly, hand apertures were affected by the illusion during pantomime grasping but not in normal grasping, indicating that displaced pantomime grasping is based on allocentric information. This was true for participants without experience in performing pantomime grasps as well as for magicians with experience in pantomiming. The finding that the illusory bias is limited to pantomime grasping and persists with experience supports the conjecture that the normal engagement of the dorsal system’s contribution requires tactile contact with a goal object. If no tactile contact is made, then movement control shifts toward the ventral system.

The Influence of the Social Environment Context in Stress and Coping in Sport

Lazarus (1999) model of stress and coping is based on the reciprocal interaction between the person and the environment. The aim of this study therefore was to examine whether the social environment (significant others) are of influence on the stress and coping of team athletes. The study consisted of two separate studies in which a total of 12 team athletes participated. First, six field hockey players (two males, four females) aged 18–29 years (M = 23.0 years) participated in a diary study. Second, six team athletes of different sports (two males, four females) aged 24–29 years (M = 25.8 years) were interviewed. The results showed that in particular teammates are important for the appraisal of stress and coping in team sports. For over half (i.e., 51.5%) of the reported stressors in the diary study the participants felt that others were of influence on their coping. Team athletes experienced the highest stress intensity during competition, or when they appraised the situation as a threat. When others were of influence the team athletes were most likely to appraise the situation as a challenge and use problem- or emotion-focused coping strategies. These finding might provide a new portal for intervention to enhance coping with stress in sport and enhance performance and satisfaction.

The influence of errors during practice on motor learning in young individuals with cerebral palsy

The aim of this study was to investigate the effect of errors during practice on motor skill learning in young individuals with cerebral palsy (CP). Minimizing errors has been validated in typically developing children and children with intellectual disabilities as a method for implicit learning, because it reduces working memory involvement during learning. The present study assessed whether a practice protocol that aims at minimizing errors can induce implicit learning in young individuals with CP as well. Accordingly, we hypothesized that reducing errors during practice would lead to enhanced learning and a decrease in the dependency of performance on working memory. Young individuals with CP practiced an aiming task following either an error-minimizing (N=20) or an error-strewn (N=18) practice protocol. Aiming accuracy was assessed in pre-, post- and retention test. Dual task performance was assessed to establish dependency on working memory. The two practice protocols did not invoke different amounts or types of learning in the participants with CP. Yet, participants improved aiming accuracy and showed stable motor performance after learning, irrespective of the protocol they followed. Across groups the number of errors made during practice was related to the amount of learning, and the degree of conscious monitoring of the movement. Only participants with relatively good working memory capacity and a poor initial performance showed a rudimentary form of (most likely, explicit) learning. These new findings on the effect of the amount of practice errors on motor learning in children of CP are important for designing interventions for children and adolescents with CP.

Implicit Goalkeeper Influences on Goal Side Selection in Representative Penalty Kicking Tasks

In well-controlled lab situations, marginal displacements of the goalkeeper on the goal line affect goal side selection of penalty takers implicitly, that is, without the penalty takers being consciously aware of the displacement. Whether this effect is retained in more representative real-life situations with competing goalkeepers and penalty takers has not been verified. In the current study, penalty takers were instructed to position the goalkeepers at the centre of the goal. They then performed penalty kicks adopting either a keeper independent or a keeper dependent strategy, while goalkeepers actually attempted to save the ball by strategically diving early or late. Analyses of trials in which penalty takers failed to place the goalkeeper in the centre of the goal (although they incorrectly believed they placed the goalkeeper at the centre of the goal) showed that implicit influences of the goalkeeper's position on goal side selection were overridden by the (conscious) perception of the direction of the goalkeeper's dive, but only if the penalty takers deliberately monitored the goalkeeper's action and the goalkeeper committed early enough for penalty takers to respond. In all other combinations of penalty kick and goalkeeper strategies more than 60% of the kicks were directed to the side of the goal with more space. Most importantly, however, the current study shows that influences of implicit perception on the penalty takers' decision making are rather pervasive considering that many supraliminal sources of information were available. That is, the current study demonstrates that implicit perception retains its influence on decision-making even if other (stronger) stimuli are also present.

Catching moving objects: Differential effects of background motion on action mode selection and movement control in 6- to 10-month-old infants

In human adults the use of visual information for selecting appropriate modes for action appears to be separate from the use of visual information for the control of movements of which the action is composed (Milner & Goodale, [1995] The visual brain in action; [2008] Neuropsychologia 46:774-785). More specifically, action mode selection primarily relies upon allocentric information, whereas movement control mainly exploits egocentric information. In the present study, we investigated to what degree this division is already present in 6- to 10-month-old infants when reaching for moving objects; that is, whether allocentric information is uniquely exploited for action mode selection (i.e., reaching with one or the other hand) or whether it is also used for movement control (i.e., reaching kinematics). Infants were presented with laterally approaching objects at two speeds (i.e., 20 and 40 cm/s) against a stationary or moving background. Background motion affects allocentric information about the object's velocity relative to its background. Results indicated that object speed constrained both infants' action mode selection and movement control. Importantly, however, the influence of background motion was limited to action mode selection and did not extend to movement control. The findings provide further support for the contention that during early development information usage is--at least to some degree--separated for action mode selection and movement control.

Current insights in the development of children's motor imagery ability

Over the last two decades, the number of studies on motor imagery in children has witnessed a large expansion. Most studies used the hand laterality judgment paradigm or the mental chronometry paradigm to examine motor imagery ability. The main objective of the current review is to collate these studies to provide a more comprehensive insight in children’s motor imagery development and its age of onset. Motor imagery is a form of motor cognition and aligns with forward (or predictive) models of motor control. Studying age-related differences in motor imagery ability in children therefore provides insight in underlying processes of motor development during childhood. Another motivation for studying age-related differences in motor imagery is that in order to effectively apply motor imagery training in children (with motor impairments), it is pertinent to first establish the age at which children are actually able to perform motor imagery. Overall, performance in the imagery tasks develops between 5 and 12 years of age. The age of motor imagery onset, however, remains equivocal, as some studies indicate that children of 5 to 7 years old can already enlist motor imagery in an implicit motor imagery task, whereas other studies using explicit instructions revealed that children do not use motor imagery before the age of 10. From the findings of the current study, we can conclude that motor imagery training is potentially a feasible method for pediatric rehabilitation in children from 5 years on. We suggest that younger children are most likely to benefit from motor imagery training that is presented in an implicit way. Action observation training might be a beneficial adjunct to implicit motor imagery training. From 10 years of age, more explicit forms of motor imagery training can be effectively used.

Predictive models to determine imagery strategies employed by children to judge hand laterality

A commonly used paradigm to study motor imagery is the hand laterality judgment task. The present study aimed to determine which strategies young children employ to successfully perform this task. Children of 5 to 8 years old (N = 92) judged laterality of back and palm view hand pictures in different rotation angles. Response accuracy and response duration were registered. Response durations of the trials with a correct judgment were fitted to a-priori defined predictive sinusoid models, representing different strategies to successfully perform the hand laterality judgment task. The first model predicted systematic changes in response duration as a function of rotation angle of the displayed hand. The second model predicted that response durations are affected by biomechanical constraints of hand rotation. If observed data could be best described by the first model, this would argue for a mental imagery strategy that does not involve motor processes to solve the task. The second model reflects a motor imagery strategy to solve the task. In line with previous research, we showed an age-related increase in response accuracy and decrease in response duration in children. Observed data for both back and palm view showed that motor imagery strategies were used to perform hand laterality judgments, but that not all the children use these strategies (appropriately) at all times. A direct comparison of response duration patterns across age sheds new light on age-related differences in the strategies employed to solve the task. Importantly, the employment of the motor imagery strategy for successful task performance did not change with age.