Is optimal vision required for the successful execution of an interceptive task?

The importance of optimal visual function in demanding interceptive tasks is far from established. The aim of the study was to determine whether induced myopic blur and hence sub-optimal visual function would give rise to a detrimental effect on performance in the execution of an interceptive task. The batting performance of grade level cricket players was assessed facing a bowling machine whilst wearing contact lenses of four different refractive conditions (plano (nil), +1.00, +2.00 and +3.00D over-refraction), inducing increasing amounts of myopic blur. Performance for each condition was assessed based both on the shot quality against each delivery judged by a qualified cricket coach blind to each condition, along with an evaluation of the quality of ball-bat contact for each delivery. No significant change was found in batting performance with the introduction of +1.00 and +2.00D of induced myopic blur. A +3.00D over-correction was required before any significant decrease in batting performance was detected, demonstrating that batters needed to be essentially legally blind (as simulated through the use of the +3.00D over-refraction) before there was any significant measurable decrement in batting performance. We concluded that optimal visual correction is not necessarily required for optimal performance in a demanding interceptive task, and that the human perceptual-motor system is capable of compensating for marked alterations in input.     

Indirect interception actions by blind and visually impaired perceivers: Echolocation for interceptive actions

Vernat, J.-P. & Gordon, M. S. (2010). Indirect interception actions by blind and visually impaired perceivers: Echolocation for interceptive actions. Scandinavian Journal of Psychology, 51, 75–83.
This research examined the acoustic information used to support interceptive actions by the blind. Congenitally blind and severely visually impaired participants (all wearing an opaque, black eye-mask) were asked to listen to a target ball rolling down a track. In response, participants rolled their own ball along a perpendicular path to intercept the target. To better understand what information was used the echoic conditions and rolling dynamics of the target were varied across test sessions. In addition the rolling speed of the target and the distance of the participant from the target were varied across trials. Results demonstrated that participants tended to perform most accurately at moderate speeds and distances, overestimating the target's arrival at the fastest speed, and underestimating it at the slowest speed. However, changes to the target's dynamics, that is, the amount of deceleration it underwent on approach, did not strongly influence performance. Echoic conditions were found to affect performance, as participants were slightly more accurate in conditions with faster, higher-intensity echoes. Based on these results blind individuals in this research seemed to be using spatial and temporal cues to coordinate their interceptive actions.     

Indirect interception actions by blind and sighted perceivers: The role of modality and tau

Vernat, J.‐P. & Gordon, M.S. (2011). Indirect interception actions by blind and sighted perceivers: The role of modality and tau. Scandinavian Journal of Psychology 52, 83–92. Acoustic and visual interceptive actions were tested in this research by comparing the performance of blind, blind‐folded, and sighted individuals. An indirect interception method was employed in which the participant had to roll an intercepting ball towards a moving target on a perpendicular track. The interception task used conditions that varied the speed, rolling distance, and target size/intensity. While performance was highly consistent and accurate for visual participants in this research, the blind and blind‐folded participants demonstrated much more performance variability in response to changes in speed and distance. Manipulation of target size and intensity did not affect judgments, however performance tended to be more accurate at shorter distances and with faster target speeds. Results from this research are discussed in terms of their implications for tau in acoustic interception, and the use of spatial and temporal cues for guiding interceptive actions.     

Three- to eight-month-old infants' catching under monocular and binocular vision

We report a cross-sectional and a longitudinal experiment that examined developmental changes in the relative contribution of monocular and binocular variables in the guidance of interceptive arm movements. Three- to eight-month-old infants were observed while presented with differently sized balls that approached frontally with a constant velocity under both monocular and binocular viewing conditions. Movement onset indicated that with age infants increasingly came to rely on binocular variables in controlling the timing of the interceptive arm movements. That is, from 7 to 8 months of age movement onset was independent from object size under binocular but not under monocular viewing. In contrast, binocular viewing enhanced the spatial accuracy of the interceptive arm movements at all ages. We concluded that attunement to binocular information is a key process in infants' gaining adaptive control of goal-directed arm movements. However, interceptive arm movements entail the formation of multiple on-line couplings between optic and movement variables, each of which appears to develop at its own pace.     

Systems factorial technology provides novel insights into the cognitive processing characteristics of open-skill athletes

Sport expertise has been shown to modulate the cognitive advantage in open-skill athletes, with evidence for a greater advantage for athletes practicing interceptive sports relative to strategic sports. However, this conclusion is solely based on central tendency measures such as accuracy or mean reaction time (RT), dismissing important information embedded in the intra-individual temporal dynamics of cognitive performance. This study aimed to better understand the cognitive advantage associated with open-skill sports, with a non-parametric approach assessing cognitive process at the level of RT distribution (i.e., systems factorial technology, SFT). Twenty-eight interceptive sport athletes, 27 strategic sport athletes, and 26 physically active non-athletes performed a go/nogo version of the redundant target task to assess their processing capacity of simultaneously monitoring multiple information channels. SFT was applied to assess resilience capacity, an estimate of workload capacity underlying inhibitory control. Our findings showed that interceptive sport athletes exhibited shorter mean RT relative to non-athletes selectively in the task condition involving distracting information, while strategic sport athletes showed greater resilience capacity over earlier responses relative to the other groups. These findings suggest that the two types of open-skill sports may be associated with different processing specificity, possibly reflecting the domain-specific rules and requirements.     

The influence of ball-swing on the timing and coordination of a natural interceptive task

Successful interception relies on the use of perceptual information to accurately guide an efficient movement strategy that allows performers to be placed at the right place at the right time. Although previous studies have highlighted the differences in the timing and coordination of movement that underpin interceptive expertise, very little is known about how these movement patterns are adapted when intercepting targets that follow a curvilinear flight-path. The aim of this study was to examine how curvilinear ball-trajectories influence movement patterns when intercepting a fast-moving target. Movement timing and coordination was examined when four groups of cricket batters, who differed in their skill level and/or age, hit targets that followed straight or curvilinear flight-paths. The results revealed that when compared to hitting straight trials, (i) mixing straight with curvilinear trials altered movement coordination and when the ball was hit, (ii) curvilinear trajectories reduced interceptive performance and significantly delayed the timing of all kinematic moments, but there were (iii) larger decrease in performance when the ball swung away from (rather than in towards) the performer. Movement coordination differed between skill but not age groups, suggesting that skill-appropriate movement patterns that are apparent in adults may have fully emerged by late adolescence.     

Ecological relevance of stereopsis in one-handed ball-catching

The aim of this study was to compare one-handed catching performance between catchers with high (n = 10) and low (n = 10) binocular depth vision or stereopsis. In two sessions of 90 trials, tennis balls were projected at three different velocities towards the subject's shoulder region. Participants with good stereopsis were more successful, although the difference in number of correct catches fell short of significance. More specifically, catchers with low stereopsis made more temporal errors, but no differences in spatial errors. As the velocity of the ball increased, the initiation of the catch was delayed and catching performance decreased. The finding that stereopsis affected timing of the catch challenges the 'monocular tau hypothesis' in the control of interceptive timing, while the velocity effect shows that the act of catching a ball is not initiated at a constant time-to-contact.     

Visual information underpinning skilled anticipation: The effect of blur on a coupled and uncoupled in situ anticipatory response

Coupled interceptive actions are understood to be the result of neural processing—and visual information— which is distinct from that used for uncoupled perceptual responses. To examine the visual information used for action and perception, skilled cricket batters anticipated the direction of balls bowled toward them using a coupled movement (an interceptive action that preserved the natural coupling between perception and action) or an uncoupled (verbal) response, in each of four different visual blur conditions (plano, +1.00, +2.00, +3.00). Coupled responses were found to be better than uncoupled ones, with the blurring of vision found to result in different effects for the coupled and uncoupled response conditions. Low levels of visual blur did not affect coupled anticipation, a finding consistent with the comparatively poorer visual information on which online interceptive actions are proposed to rely. In contrast, some evidence was found to suggest that low levels of blur may enhance the uncoupled verbal perception of movement.     

Psycho-perceptual-motor skills are deemed critical to save the penalty corner in international field hockey

In interceptive sports such as field hockey goalkeeping, the psycho-perceptual-motor skill anticipation is vital for performance due to the extreme time constraints associated with saving a goal. The purpose of this study was to understand the beliefs and attitudes of international field hockey goalkeepers and coaches regarding anticipation of the drag-flick in penalty corners. Seven international goalkeepers and five international coaches were interviewed. Using a constructionist and relativist approach to reflexive thematic data analysis, we identified three overarching themes to anticipate the drag-flick, namely, pre-match video analysis, perception and action, and psychological factors. In the first theme, participants reported that pre-match video analysis allowed goalkeepers and coaches to identify the attacking capabilities of opposing teams. This analysis was used to inform defensive structure and save the drag-flick. In the second theme, participants reported that perception and action, which consisted of the pick-up of visual cues and movement execution, was important to anticipate the drag-flick. Goalkeepers reported that they rely heavily on ball flight, which was central in coaches’ approaches in training drills such as to use a projection machine that presents only ball flight information. The third theme, psychological factors, encompassed, psychological resilience, arousal regulation, leadership and communication, and sports intelligence, which were thought to be vital to facilitate anticipation of the drag-flick. The findings of this study have important implications for how to assess and train visual anticipation in time-constrained interceptive sports skills.     

Analysis of recent empirical challenges to an account of interceptive timing.

How do we perceive how long it will be before we reach a certain place when running, driving, or skiing? How do we perceive how long it will be before a moving object reaches us or will arrive at a place where it can be hit or caught? These are questions of how we temporally coordinate our actions with a dynamic environment so as to control collision events. Much of the theoretical work on the control of these interceptive actions has been united in supposing that (1) timing is functionally separable from positioning and the two are controlled using different types of information; (2) timing is controlled using special-purpose time-to-arrival information; (3) the time-to-arrival information used for the timing of fast interceptive actions is a first-order approximation to the actual time-to-arrival, which does not take accelerations into account. Challenges to each of these suppositions have recently emerged, suggesting that a complete rethinking of how interceptions are controlled may be necessary. These challenges are analyzed in detail and it is shown that they are readily accommodated by a recent theory of interceptive timing based on the points just noted.     

Analysis of recent empirical challenges to an account of interceptive timing

How do we perceive how long it will be before we reach a certain place when running, driving, or skiing? How do we perceive how long it will be before a moving object reaches us or will arrive at a place where it can be hit or caught? These are questions of how we temporally coordinate our actions with a dynamic environment so as to control collision events. Much of the theoretical work on the control of these interceptive actions has been united in supposing that (1) timing is functionally separable from positioning and the two are controlled using different types of information; (2) timing is controlled using special-purpose time-to-arrival information; (3) the time-to-arrival information used for the timing of fast interceptive actions is a first-order approximation to the actual time-to-arrival, which does not take accelerations into account. Challenges to each of these suppositions have recently emerged, suggesting that a complete rethinking of how interceptions are controlled may be necessary. These challenges are analyzed in detail and it is shown that they are readily accommodated by a recent theory of interceptive timing based on the points just noted.     

Perception-action coupling and expertise in interceptive actions

The goal of this experiment was to show that expertise in interceptive actions can be explained by a shorter delay in movement regulation. In this contribution, we tested tennis experts and non-experts using a simulated interceptive task. The experimental device simulated linear motion of an object toward a target on a horizontal runway. Participants had to intercept the simulated moving object with their right hand holding a cart that could slide along a horizontal track perpendicular to the runway. Three different velocity conditions were used: a constant velocity condition that maintained the initial velocity (2m/s) constant until arriving on the target; the decelerated and accelerated velocity conditions, in which the velocity suddenly changed (400 ms before its arrival on the target) from 2 to 1m/s or 3m/s, respectively. Timing accuracy and movement correction after the unexpected velocity change were analysed. The experts were more accurate in the decelerative case (-29 and -124 ms respectively), in the accelerative case (69 and 116 ms respectively), but not in the constant velocity case (2 and 13 ms respectively). Findings can be explained by the shorter visuo-motor delay (VMD: the time required to adapt the movement to the new velocity) for the experts (162 ms) than for the non-experts (221 ms). This shorter VMD offers more time to adapt the interceptive movement to the new velocity. These results can be interpreted as an optimization of the perception-action coupling with expertise.     

Neurophysiological evidence of how quiet eye supports motor performance

Prolonged quiet eye (QE) duration is associated with greater performance in various types of targeting and interceptive tasks. However, the mechanism by which QE affects performance remains debatable. This study aimed to test the validity of the pre-programming and online control hypotheses using electromyography (EMG), electrooculography (EOG) and electroencephalography (EEG) during a golf putting task. Twenty-one college students were recruited for this study. Each participant performed 100 golf putting trials during which the putting performance, EMG, EOG, and EEG signals were recorded. The QE duration including the pre- and post-movement initiation components, and movement-related cortical potentials (MRCPs) were analyzed off-line. We found that successful putts were associated with longer QEtotal (the total QE duration from QE onset to QE offset), QEpre (QE occurring before movement initiation), and QEpost (QE occurring after movement initiation) durations than failed putts. Greater cortical activation in the MRCPs was observed within the prefrontal, premotor, and parietal cortices during successful putts compared with failed putts. These findings suggest that QE serves both pre-programming and online control roles in supporting golf putting performance.

     

Evidence for a generic interceptive strategy

In the present work, we first clarify a more precise definition of instantaneous optical angles in control tasks such as interception. We then test how well two interceptive strategies that have been proposed for catching fly balls account for human Frisbee-catching behavior. The first strategy is to maintain the ball's image along a linear optical trajectory (LOT). The second is to keep vertical optical ball velocity decreasing while maintaining constant lateral optical velocity. We found that an LOT accounted for an average of over 96% of the variance in optical Frisbee movement, while maintenance of vertical and lateral optical velocities was random. This work confirms a common interception strategy used across interceptive tasks, extending to complex target trajectories.     

Did you see that? Dissociating advanced visual information and ball flight constrains perception and action processes during one-handed catching

The integration of separate, yet complimentary, cortical pathways appears to play a role in visual perception and action when intercepting objects. The ventral system is responsible for object recognition and identification, while the dorsal system facilitates continuous regulation of action. This dual-system model implies that empirically manipulating different visual information sources during performance of an interceptive action might lead to the emergence of distinct gaze and movement pattern profiles. To test this idea, we recorded hand kinematics and eye movements of participants as they attempted to catch balls projected from a novel apparatus that synchronised or de-synchronised accompanying video images of a throwing action and ball trajectory. Results revealed that ball catching performance was less successful when patterns of hand movements and gaze behaviours were constrained by the absence of advanced perceptual information from the thrower's actions. Under these task constraints, participants began tracking the ball later, followed less of its trajectory, and adapted their actions by initiating movements later and moving the hand faster. There were no performance differences when the throwing action image and ball speed were synchronised or de-synchronised since hand movements were closely linked to information from ball trajectory. Results are interpreted relative to the two-visual system hypothesis, demonstrating that accurate interception requires integration of advanced visual information from kinematics of the throwing action and from ball flight trajectory.     

Gender-specific movement strategies using a computer-pointing task

Females typically demonstrate a movement time advantage for tasks requiring high levels of manual dexterity, whereas males are notably better at targeting activities. According to D. Kimura (2000), the hunter-gatherer hypothesis primarily accounts for those performance advantages; that dichotomy fails, however, when one makes movement outcome predictions for tasks that are not clearly fine-motor or interceptive in nature. Investigators have recently proposed that time constraints (M. Peters, 2005) and gender-specific response style differences (M. Peters & P. Campagnaro, 1996; L. E. Rohr, 2006) affect motor performance. Here, the author used a computer-pointing task measuring both movement error and movement time in 16 participants to further investigate response style differences. Kinematic and linear regression analyses between resultant error and both movement time and task difficulty reinforced the notion that gender-specific movement biases emphasize speed and accuracy, respectively, for men and women.     

Gender-Specific Movement Strategies Using a Computer-Pointing Task

Females typically demonstrate a movement time advantage for tasks requiring high levels of manual dexterity, whereas males are notably better at targeting activities. According to D. Kimura (2000), the hunter-gatherer hypothesis primarily accounts for those performance advantages; that dichotomy fails, however, when one makes movement outcome predictions for tasks that are not clearly fine-motor or interceptive in nature. Investigators have recently proposed that time constraints (M. Peters, 2005) and gender-specific response style differences (M. Peters & P. Campagnaro, 1996; L. E. Rohr, 2006) affect motor performance. Here, the author used a computer-pointing task measuring both movement error and movement time in 16 participants to further investigate response style differences. Kinematic and linear regression analyses between resultant error and both movement time and task difficulty reinforced the notion that gender-specific movement biases emphasize speed and accuracy, respectively, for men and women.     

Perception-action coupling and anticipatory performance in baseball batting

The authors examined 10 expert and 10 novice baseball batters' ability to distinguish between a fastball and a change-up in a virtual environment. They used 2 different response modes: (a) an uncoupled response in which the batters verbally predicted the type of pitch and (b) a coupled response in which the batters swung a baseball bat to try and hit the virtual ball. The authors manipulated visual information from the pitcher and ball in 6 visual conditions. The batters were more accurate in predicting the type of pitch when the response was uncoupled. In coupled responses, experts were better able to use the first 100 ms of ball flight independently of the pitcher's kinematics. In addition, the skilled batters' stepping patterns were related to the pitcher's kinematics, whereas their swing time was related to ball speed. Those findings suggest that specific task requirements determine whether a highly coupled perception-action environment improves anticipatory performance. The authors also highlight the need for research on interceptive actions to be conducted in the performer's natural environment.     

Interference effects on preschool children's learning sets

Four experiments investigated interference in 5-year-olds' learning sets. Experiment 1 manipulated intertrial and interproblem intervals, showing that increased intertrial intervals retarded performance. Long interproblem intervals interacted with short intertrial intervals to produce performance facilitation. Experiment 2 investigated interpolations within problems with either similar or dissimilar stimulus presentations. Similar stimuli caused greater performance decrements than dissimilar. Experiment 3 hypothesized that the within-subjects design of Experiment 1 masked interproblem interval effects. Testing between-subjects established that increased interproblem delays facilitate performance. In Experiment 4 interproblem delays were further tested in a series of shifts within and between dimensions. Increased delays more greatly benefited shifts within dimensions. It is concluded that intertrial and interproblem intervals affect learning set performance differentially. Intertrial delays result in performance deterioration due in part to interference. Interproblem delays facilitate performance at least in part by providing the opportunity for suppression of proactive interference, and perhaps in part by providing the opportunity for constructive cognitive processing.     

Muscular proprioception contributes to the control of interceptive actions

The authors proposed a model of the control of interceptive action over a ground plane (Chardenon, Montagne, Laurent, & Bootsma, 2004). This model is based on the cancellation of the rate of change of the angle between the current position of the target and the direction of displacement (i.e., the bearing angle). While several sources of visual information specify this angle, the contribution of proprioceptive information has not been directly tested. In this study, the authors used a virtual reality setup to study the role of proprioception when intercepting a moving target. In a series of experiments, the authors manipulated proprioceptive information by using the tendon vibration paradigm. The results revealed that proprioception is crucial not only to locate a moving target with respect to the body but also, and more importantly, to produce online displacement velocity changes to intercept a moving target. These findings emphasize the importance of proprioception in the control of interceptive action and illustrate the relevance of our model to account for the regulations produced by the participants.