Prefrontal cortex activity and functional organisation in dual-task ocular pursuit is affected by concurrent upper limb movement.

Tracking a moving object with the eyes seems like a simple task but involves areas of prefrontal cortex (PFC) associated with attention, working memory and prediction. Increasing the demand on these processes with secondary tasks can affect eye movements and/or perceptual judgments. This is particularly evident in chronic or acute neurological conditions such as Alzheimer's disease or mild traumatic brain injury. Here, we combined near infrared spectroscopy and video-oculography to examine the effects of concurrent upper limb movement, which provides additional afference and efference that facilitates tracking of a moving object, in a novel dual-task pursuit protocol. We confirmed the expected effects on judgement accuracy in the primary and secondary tasks, as well as a reduction in eye velocity when the moving object was occluded. Although there was limited evidence of oculo-manual facilitation on behavioural measures, performing concurrent upper limb movement did result in lower activity in left medial PFC, as well as a change in PFC network organisation, which was shown by Graph analysis to be locally and globally more efficient. These findings extend upon previous work by showing how PFC is functionally organised to support eye-hand coordination when task demands more closely replicate daily activities.

Observational learning of atypical biological kinematics in autism.

Observing and voluntarily imitating the biological kinematics displayed by a model underpins the acquisition of new motor skills via sensorimotor processes linking perception with action. Differences in voluntary imitation in autism could be related to sensorimotor processing activity during action-observation of biological motion, as well as how sensorimotor integration processing occurs across imitation attempts. Using an observational practice protocol, which minimized the active contribution of the peripheral sensorimotor system, we examined the contribution of sensorimotor processing during action-observation. The data showed that autistic participants imitated both the temporal duration and atypical kinematic profile of the observed movement with a similar level of accuracy as neurotypical participants. These findings suggest the lower-level perception-action processes responsible for encoding biological kinematics during the action-observation phase of imitation are operational in autism. As there was no task-specific engagement of the peripheral sensorimotor system during observational practice, imitation difficulties in autism are most likely underpinned by sensorimotor integration issues related to the processing of efferent and (re)afferent sensorimotor information during trial-to-trial motor execution.

Does the threat of COVID-19 modulate automatic imitation?

The tendency to involuntarily imitate the actions of others (automatic imitation) can be modulated by social affiliative cues. Here, we explored whether the disruption to our social lives caused by the COVID-19 pandemic may subsequently influence automatic imitation. Three groups were initially presented a sentence comprehension task that featured either neutral (control), safe or unsafe primes to COVID-19 infection. They then completed an automatic imitation task, where a numeric cue was presented alongside apparent motion of an index or middle finger, which was either compatible or incompatible with the required response. Reaction times were longer for the incompatible compared to compatible trials, and thus demonstrated automatic imitation. However, there was no influence of the primes indicating that automatic imitation was unaffected by the risk of COVID-19. The potential theoretical explanations and practical implications of pathogen avoidance and social bonding incentives are discussed with reference to pandemic events.

Virtual reality boxing: Gaze-contingent manipulation of stimulus properties using blur.

It has been reported that behavior of experts and novices in various sporting tasks is impervious to the introduction of blur. However, studies have used diverse methods of blurring the visual stimulus (i.e., dioptric blur and Gaussian blur), and tasks that did not always preserve the normal perception-action coupling. In the current study, we developed a novel experimental protocol to examine the effect of different levels of Gaussian blur on interception performance and eye gaze data using an immersive VR task. Importantly, this provided a realistic simulation of a real-world boxing scenario (e.g., the presence of a feint prior to the onset of different combinations of punches) in which expert combat athletes (n = 18) experienced a first-person, adaptive viewpoint of the visual environment, which could be blurred according to their gaze location (central blur, peripheral blur, no blur). We found that participants exhibited similar interception performance in the presence of central blur or peripheral blur compared to a control condition with no blur. However, interception performance was significantly better with a central blur compared to peripheral blur. Eye gaze data indicated that although participants fixated at similar areas of interest irrespective of the presence of blur, fixation duration was significantly longer with a strong level of blur in the peripheral viewing condition than all levels of central blur and the control condition. These findings can be explained by relocating attention to different areas of the environment, which thereby influenced the perception of salient information. Participants also performed better on the first punch of a sequence preceded by a foot feint compared to arm feint or no feint. Still, irrespective of feint type, performance was significantly better on the second and third punch compared to the first punch. These findings are consistent with participants using additional information from the opponent's body movements and situational probabilities to increase performance as the sequence of punches developed. Overall, these are the first evidence for the use of VR as a means to examine gaze-contingent manipulations of the environment, and hence highlight the potential for facilitating learning and transfer to a real sporting situations.

Online control of rapid target-directed aiming using blurred visual feedback.

The accuracy and precision of target-directed aiming is contingent upon the availability of online visual feedback. The present study aimed to examine the visual regulation of aiming with blurred vision. The aiming task was executed using a stylus on a graphics digitizing board, which was translated onto a screen in the form of a cursor (representing the moving limb) and target. The vision conditions involved the complete disappearance or blur of the cursor alone, target alone, and cursor+target. These conditions involved leaving the screen uncovered or covering with a diffusing sheet to induce blur. The distance between the screen and sheet was increased to make the blur progressively more severe (0 cm, 3 cm). Results showed significantly less radial and variable error under blurred compared to no vision of the cursor and cursor+target. These findings were corroborated by the movement kinematics including a shorter proportion of time to peak velocity, more negative within-participant correlation between the distances travelled to and after peak velocity, and lower spatial variability from peak velocity to the end of the movement under blurred vision. The superior accuracy and precision under the blurred compared to no vision conditions is consistent with functioning visual regulation of aiming, which is primarily contingent upon the online visual feedback of the moving limb. This outcome may be attributed to the processing of low spatial-high temporal frequencies. Potential implications for low vision diagnostics are discussed.

Effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness: A multi-country cluster randomized controlled trial.

PURPOSE: To examine the effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness in children aged 7-8 years. METHODS: Twenty schools in 5 different European countries (2 second-grade classrooms per school) participated in a cluster randomized controlled trial (Sport at School trial). Participants were assigned to either a control group, which continued with their habitual physical education lessons, or to an intervention group, which replaced these lessons with a 1-year karate intervention (Karate Mind and Movement program). A total of 721 children (344 girls and 377 boys, 7.4 ± 0.5 years old, mean ± SD) completed the study, of which 333 and 388 were assigned to the control group and intervention group, respectively. Outcomes included academic performance (average grade), psychosocial functioning (Strengths and Difficulties Questionnaire for parents), and different markers of physical fitness (cardiorespiratory fitness, balance, and flexibility). RESULTS: The intervention provided small but significant benefits compared to the control group for academic achievement (d = 0.16; p = 0.003), conduct problems (d = -0.28; p = 0.003), cardiorespiratory fitness (d = 0.36; p < 0.001), and balance (d = 0.24; p = 0.015). There was a trend towards significant benefits for flexibility (d = 0.24; p = 0.056). No significant benefits were observed for other variables, including psychosocial difficulties, emotional symptoms, hyperactivity/inattention, peer problems, or prosocial behaviour (all p > 0.05). CONCLUSION: A 1-year school-based karate intervention was effective in improving academic achievement, conduct problems, and physical fitness in primary school children. The results support the inclusion of karate during physical education lessons.

Visual Cognition and Experience Mediate the Relation between Age and Decision Making in Youth Volleyball Players.

SIGNIFICANCE: Experts in different sports show superior decision-making skills compared with novices, but little is known about its development in youth players. This study shows that the age-related improvements in visual cognition and accumulation of sport-specific experience explain a considerable amount of the development in decision making in volleyball. PURPOSE: The aim of this study was to investigate the mediating effects of visual cognition and volleyball experience on the relationship between age and decision making in youth volleyball players. METHODS: A total of 171 female volleyball players aged 6 to 17 years performed a sport-specific, video-based test of decision making, as well as four different visual cognition tests. Using structural equation modeling, we examined if volleyball experience and a latent variable constructed from the four tests of visual cognition act as parallel mediators in the association between age and decision making. RESULTS: The parallel multiple mediation model for the association between age and decision making was supported in youth volleyball players. Moreover, significant indirect effects and a nonsignificant direct effect indicated that visual cognition and experience fully mediated the relation between age and decision making and together explain 38% of the variance in decision-making performance. The effects of both mediators were not significantly different, and there was no residual correlation between experience and visual cognition, which indicates that these mediators are unrelated to each other. CONCLUSIONS: Our findings demonstrate that visual cognition and volleyball experience mediate the relation between age and decision making independently, which indicates that they each influence different parts of the decision-making process. These results highlight the importance of the development of perceptual-cognitive skill in young players, and future research should further investigate the development of these skills as well as their underlying factors in different kinds of sports.

Effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness: A multi-country cluster randomized controlled trial.

PURPOSE: To examine the effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness in children aged 7-8 years. METHODS: Twenty schools in 5 different European countries (2 second-grade classrooms per school) participated in a cluster randomized controlled trial (Sport at School trial). Participants were assigned to either a control group, which continued with their habitual physical education lessons, or to an intervention group, which replaced these lessons with a 1-year karate intervention (Karate Mind and Movement program). A total of 721 children (344 girls and 377 boys, 7.4 ± 0.5 years old, mean ± standard deviation) completed the study, of which 333 and 388 were assigned to the control group and intervention group, respectively. Outcomes included academic performance (average grade), psychosocial functioning (Strengths and Difficulties Questionnaire for parents), and different markers of physical fitness (cardiorespiratory fitness, balance, and flexibility). RESULTS: The intervention provided small but significant benefits compared to the control group for academic achievement (d = 0.16; p = 0.003), conduct problems (d = -0.28; p = 0.003), cardiorespiratory fitness (d = 0.36; p < 0.001), and balance (d = 0.24; p = 0.015). There was a trend towards significant benefits for flexibility (d = 0.24; p = 0.056). No significant benefits were observed for other variables, including psychosocial difficulties, emotional symptoms, hyperactivity/inattention, peer problems, or prosocial behavior (all p > 0.05). CONCLUSION: A 1-year school-based karate intervention was effective in improving academic achievement, conduct problems, and physical fitness in primary school children. The results support the inclusion of karate during physical education lessons.

Children Involved in Team Sports Show Superior Executive Function Compared to Their Peers Involved in Self-Paced Sports.

Children's motor and cognitive functions develop rapidly during childhood. Physical activity and executive function are intricately linked during this important developmental period, with physical activity interventions consistently proving to benefit children's executive function. However, it is less clear which type of physical activity shows the strongest associations with executive function in children. Therefore, this study compared executive function performance of children aged 8 to 12 that either participated in team sports or self-paced sports or were not involved in any kind of organized sports (non-athletes). Results demonstrate that children participating in team sports show superior executive function compared to children participating in self-paced sports and non-athletes. Importantly, children participating in self-paced sports do not outperform non-athletes when it comes to executive function. This study is the first to show that even at a very young age, team sports athletes outperform athletes from self-paced sports as well as non-athletes on a multifaceted and comprehensive test battery for executive function. Furthermore, our findings support the hypothesis that cognitively engaging physical activity, such as participation in team sports, might show stronger associations with executive functioning compared to other types of sports and physical activity.

The development of perceptual-cognitive skills in youth volleyball players.

In many sports, elite players outperform novices on tests for perceptual-cognitive skills, such as anticipation, decision-making and pattern recall. However, the developmental trajectory of these perceptual-cognitive skills has received limited attention. Therefore, this study examined the development of anticipation, decision-making and pattern recall in 202 female volleyball players aged between 7 and 26 years old. Participants were categorized into six age groups: U9, U11, U13, U15, U17 and Seniors. Using a video-based occlusion protocol, we assessed participants' ability to predict pass direction, decide the most optimal attack zone, or recall the opponents' defence positions. The results demonstrated that U17 and adult players had superior accuracy and shorter response times than younger players on all three tests. Notably, U9 players performed worse than older players on all tests. Binomial distributions showed that decision-making was above chance for U17 players and adults, whereas anticipation was above chance for almost all players. Our findings indicate that age-related improvements of perceptual-cognitive skills are evident at 11 years old. However, decision-making seems to develop considerably later than anticipation and pattern recall, suggesting different developmental trajectories for the different perceptual-cognitive skills. Longitudinal research regarding the development of perceptual-cognitive skills and their underlying mechanisms is warranted, as this could have important implications for talent detection and development.

Intermittent Vision and Goal-Directed Movement: A Review.

It is well known that vision makes an important contribution to the control of goal-directed movements. However, task performance can be maintained when vision is interrupted, such as when a goalkeeper faces a free kick in soccer and the ball moves behind teammates and opposing players. To maintain behavior, it is necessary to process the visual information available from intermittent samples. In this review, we consider the performance and learning effects of intermittent vision in tasks such as aiming, reaching and grasping, goal-directed locomotion and ball-catching. We review research that finds both interocular and intraocular integration contribute to continuous upper limb control with intermittent visual pickup/sampling. Recent work using intermittent visual presentation (i.e., stroboscopic vision) to facilitate learning of general and task-specific visual-motor skills indicates that training/learning protocols that challenge, but don't alter, the visual-motor processing associated with a specific visual-motor task can be effective. In this theoretical context, we discuss methodological and design factors that could impact the effectiveness of future training studies.

The multiple process model of goal-directed aiming/reaching: insights on limb control from various special populations.

Several years ago, our research group forwarded a model of goal-directed reaching and aiming that describes the processes involved in the optimization of speed, accuracy, and energy expenditure Elliott et al. (Psychol Bull 136:1023-1044, 2010). One of the main features of the model is the distinction between early impulse control, which is based on a comparison of expected to perceived sensory consequences, and late limb-target control that involves a spatial comparison of limb and target position. Our model also emphasizes the importance of strategic behaviors that limit the opportunity for worst-case or inefficient outcomes. In the 2010 paper, we included a section on how our model can be used to understand atypical aiming/reaching movements in a number of special populations. In light of a recent empirical and theoretical update of our model Elliott et al. (Neurosci Biobehav Rev 72:95-110, 2017), here we consider contemporary motor control work involving typical aging, Down syndrome, autism spectrum disorder, and tetraplegia with tendon-transfer surgery. We outline how atypical limb control can be viewed within the context of the multiple-process model of goal-directed reaching and aiming, and discuss the underlying perceptual-motor impairment that results in the adaptive solution developed by the specific group.

Faster visual reaction times in elite athletes are not linked to better gaze stability.

The issue of whether visually-mediated, simple reaction time (VRT) is faster in elite athletes is contentious. Here, we examined if and how VRT is affected by gaze stability in groups of international cricketers (16 females, 28 males), professional rugby-league players (21 males), and non-sporting controls (20 females, 30 males). VRT was recorded via a button-press response to the sudden appearance of a stimulus (circular target-diameter 0.8°), that was presented centrally, or 7.5° to the left or right of fixation. The incidence and timing of saccades and blinks occurring from 450 ms before stimulus onset to 225 ms after onset were measured to quantify gaze stability. Our results show that (1) cricketers have faster VRT than controls; (2) blinks and, in particular, saccades are associated with slower VRT regardless of the level of sporting ability; (3) elite female cricketers had steadier gaze (fewer saccades and blinks) compared to female controls; (4) when we accounted for the presence of blinks and saccades, our group comparisons of VRT were virtually unchanged. The stability of gaze is not a factor that explains the difference between elite and control groups in VRT. Thus we conclude that better gaze stability cannot explain faster VRT in elite sports players.

The informational properties of the throwing arm for anticipation of goal-directed action.

We examined the informational value of biological motion from the arm in predicting the location of a thrown ball. In three experiments, participants were classified as being skilled and less skilled based on their actual performance on the task (i.e., using a within-task criterion). We then presented participants with a range of stick figure representations and required them to predict throw direction. In Experiment 1, we presented stick figure movies of a full body throwing action, right throwing arm plus left shoulder and throwing arm only. Participants were able to anticipate throw direction above chance under all conditions irrespective of perceptual skill level, with the perceptually skilled participants excelling under full body conditions. In Experiment 2, we neutralized dynamical differences in motion to opposing throw directions from the shoulder, elbow and wrist of the throwing arm. Neutralizing the wrist location negatively affected anticipation performance in all participants reducing accuracy to below chance. In Experiment 3, we presented movies of the motion wrist location alone and the upper section of the throwing arm (shoulder-elbow). Participants were able to successfully anticipate above chance in these latter two conditions. Our findings suggest that motion of the throwing arm contains multiple sources of information that can help facilitate the anticipation of goal-directed action. Perceptually skilled participants were superior in extracting informational value from motion at both the local and global levels when compared to less skilled counterparts.

Facilitating sensorimotor integration via blocked practice underpins imitation learning of atypical biological kinematics in autism spectrum disorder.

LAY ABSTRACT: Autistic people sometimes find it difficult to copy another person's movement accurately, especially if the movement is unfamiliar or novel (e.g. to use chop sticks). In this study, we found that autistic people were generally less accurate at copying a novel movement than non-autistic people. However, by making a small adjustment and asking people to copy this movement for a set number of attempts in a predictable manner, we showed that autistic people did successfully learn to copy a new movement. This is a very important finding for autistic people because rather than thinking they cannot copy new movements, all that needs to be considered is for parents/guardians, teachers and/or support workers to make a small adjustment so that learning occurs in a predictable manner for new skills to be successfully acquired through copying. The implications from this study are wide-ranging as copying (imitation) and motor learning are important developmental processes for autistic infants and children to acquire in order to interact within the world. Therefore, practising these behaviours in the most effective way can certainly help the developmental pathway.

Getting Off to a Shaky Start: Specificity in Planning and Feedforward Control During Sensorimotor Learning in Autism Spectrum Disorder.

Whilst autistic individuals develop new internal action models during sensorimotor learning, the acquired movements are executed less accurately and with greater variability. Such movement profiles are related to differences in sensorimotor integration and/or altered feedforward/feedback sensorimotor control. We investigated the processes underlying sensorimotor learning in autism by quantifying accuracy and variability, relative timing, and feedforward and feedback control. Although autistic individuals demonstrated significant sensorimotor learning across trials, which was facilitated by processing knowledge-of-results feedback, motor execution was less accurate than non-autistic individuals. Kinematic analysis indicated that autistic individuals showed significantly greater spatial variability at peak acceleration, but comparable spatial variability at peak velocity. These kinematic markers suggest that autistic movement profiles are driven by specific differences in sensorimotor control processes (i.e., internal action models) associated with planning and regulating the forces required to execute the movement. The reduction of variability at peak velocity indicates intact early feedback-based sensorimotor control in autism. Understanding how feedforward and feedback-based control processes operate provides an opportunity to explore how these control processes influence the acquisition of socio-motor actions in autism. Autism Res 2020, 13: 423-435. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Autistic adults successfully learned a new movement skill by physically practising it, and using feedback about how well they had done to become more accurate. When looking at the movements in detail, autistic adults were more variable than non-autistic adults when planning (e.g., how much force to use), and performing, the movement. These differences impact how autistic individuals learn different types of movement skills, which might influence how other behaviours (e.g., imitation) are acquired that support social interaction.

Stroboscopic Vision When Interacting With Multiple Moving Objects: Perturbation Is Not the Same as Elimination.

Motivated by recent findings of improved perceptual processing and perceptual-motor skill following stroboscopic vision training, the current study examined the performance and acquisition effects of stroboscopic vision methods that afford a different visual experience. In Experiment 1, we conducted a within-subject design study to examine performance of a multiple object tracking (MOT) task in different stroboscopic vision conditions (Nike Vapor Strobe®, PLATO visual occlusion, and intermittent display presentation) operating at 5.6, 3.2, or 1.8 Hz. We found that participants maintained MOT performance in the Vapor Strobe condition irrespective of strobe rate. However, MOT performance deteriorated as strobe rate was reduced in the other two stroboscopic vision conditions. Moreover, at the lowest strobe rate (1.8 Hz) there was an increase in probe reaction time, thus indicating an increased attentional demand due to the stroboscopic vision. In Experiment 2, we conducted a mixed design study to examine if practice in different stroboscopic vision conditions (Nike Vapor Strobe® and PLATO visual occlusion) influenced acquisition of a novel precision-aiming task [i.e., multiple object avoidance (MOA) task] compared to a normal vision group. Participants in the PLATO visual occlusion group exhibited worse performance during practice than the Vapor Strobe and normal vision groups. At post-test, the Vapor Strobe group demonstrated greater success and reduced end-point error than the normal vision and PLATO groups. We interpret these findings as showing that both an intermittent perturbation (Nike Vapor Strobe®) and elimination (PLATO visual occlusion and intermittent display presentation) of visual motion and form are more attention demanding (Experiment 1), however, the intermittent perturbation, but not elimination, of visual motion and form can facilitate acquisition of perceptual-motor skill (Experiment 2) in situations where it is necessary to maintain and update a spatio-temporal representation of multiple moving objects.

Atypical biological kinematics are represented during observational practice.

The present study investigated the effect of stimulus-response compatibility on the representation of atypical biological kinematics during observational practice. A compatible group observed an atypical model that moved rightward, whereas an incompatible group observed an atypical model that moved leftward. Both groups were instructed to observe the model with the intention to later reproduce the movement trajectory. This was examined in a posttest where participants were asked to move rightward with a kinematic profile that matched the atypical kinematics. Compared to a control group that did not engage in practice, and irrespective of whether the stimulus was observed in a spatially compatible or incompatible orientation, participants from both experimental groups reproduced velocity profiles that were comparable and similar to the atypical biological kinematics. Bayesian analysis indicated equality between the 2 experimental groups, thus suggesting comparable sensorimotor processing. Therefore, by rotating the incompatible stimulus by 180 degrees during observational practice, the current study has isolated the processing and representation of atypical biological kinematics to the underlying sensorimotor processes, rather than spatial encoding of peak velocity via processes associated with stimulus-response compatibility. (PsycINFO Database Record

Temporal estimation in prediction motion tasks is biased by a moving destination.

An ability to predict the time-to-contact (TTC) of moving objects that become momentarily hidden is advantageous in everyday life and could be particularly so in fast-ball sports. Prediction motion (PM) experiments have sought to test this ability using tasks where a disappearing target moves toward a stationary destination. Here, we developed two novel versions of the PM task in which the destination either moved away from (Chase) or toward (Attract) the moving target. The target and destination moved with different speeds such that collision occurred 750, 1,000 or 1,250 ms after target occlusion. To determine if domain-specific experience conveys an advantage in PM tasks, we compared the performance of different sporting groups ranging from internationally competing athletes to non-sporting controls. There was no difference in performance between sporting groups and non-sporting controls but there were significant and independent effects on response error by target speed, destination speed, and occlusion period. We simulated these findings using a revised version of the linear TTC model of response timing for PM tasks (Yakimoff, Bocheva, & Mitrania, 1987; Yakimoff, Mateeff, Ehrenstein, & Hohnsbein, 1993) in which retinal input from the moving destination biases the internal representation of the occluded target. This revision closely reproduced the observed patterns of response error and thus describes a means by which the brain might estimate TTC when the target and destination are in motion.

Asymmetrical time-to-contact error with two moving objects persists across different vertical separations.

When human observers estimate the time-to-contact (TTC) of more than one object there is an asymmetric pattern of error consistent with prioritizing the lead object at the expense of the trail object. Here, we examined TTC estimation in a prediction motion task where two objects moved along horizontal trajectories (5 or 7.5 °/s) that had different vertical separation, and thus placed specific demands on visuospatial attention. Results showed that participants were able to accurately judge arrival order, irrespective of vertical separation, in all but two conditions where the object trajectories crossed close to the arrival location. Constant error was significantly higher for the object that trailed, as opposed to led, by 250 or 500 ms. Asymmetry in constant error between the lead and trail object was not influenced by vertical separation, and was also evident across a range of arrival times. However, while the lag between the two consecutive TTC estimations was scaled to the actual difference in object arrival times, lag did increase with vertical separation. Taken together, our results confirm that TTC estimation of two moving objects in the prediction motion task suffers from an asymmetrical interference, which is likely related to factors that influence attentional allocation.