Interceptive Actions Research Articles

Prevalence of Malocclusion in 6 and 12 Year-old Schoolchildren from Choshuenco – Neltume, Chile

To develop preventive and interceptive strategies in orthodontics is necessary to know the prevalence of malocclusion of the population in which is intended to introduce these measures. The aim of this study was to determine the prevalence of malocclusion in schoolchildren of 6 and 12 year-old from Choshuenco and Neltume 2015, belonging to the commune of Panguipulli, Chile. A descriptive study of census was conducted. The total sample was 91 children and adolescents enrolled in educational institutions in the towns of Choshuenco and Neltume. A visual clinical examination was performed to determine the number of individual malocclusions according to the method of Björk et al. (1964). For data analysis descriptive statistic was performed using Excel program. Prevalence of malocclusions was 60 % at 6 years and 91.3 % at 12 years. Prevalence data exceed those reported nationwide so it is necessary to reinforce promotional measures in the population and promote preventive - interceptive actions taking place in these locations.

Interceptive action involving coordination of a target with preceding motion of the head

Interceptive action involving coordination of a target with preceding motion of the head

Bilateral dorsal fronto-parietal areas are associated with integration of visual motion information and timed motor action

Interaction with the environment often involves situations requiring visuomotor integration. For instance, in fast interceptive actions, the brain must integrate visual information of motion with the appropriate motor action. In such dynamic situation, the brain may control movement based on predictions of where the object will be in the future and when it will arrive there. Although previous studies have analyzed brain regions associated with processing visual information of motion, motor control and visuomotor integration with static objects, less is known about visuomotor integration with moving objects. In the present study we used an event-related fMRI experiment to investigate brain areas integrating visual information of motion with motor action in response to moving objects. Twenty healthy volunteers performed an interceptive task where they had to press a button in synchrony with the arrival of a horizontally moving target at a predefined location. They also performed two control tasks—simple reaction and attention to visual motion—in order to identify and exclude brain areas that would be involved in motor or visual motion processing components that are inherent to interceptive tasks. Through a conjunction analysis, we show greater BOLD signal in a bilateral dorsal fronto-parietal network, as well as the intraparietal sulcus, angular gyrus, and human visual motion area hV5+. We discuss these results with respect to their previously identified functions, and suggest they play a role in visuomotor integration with moving objects.

Spatial Information is Exploited to Adjust Hand Movement When Hitting Moving Target

When hitting a moving target, hand movement has to be adjusted according to online information. But it is not clear whether other information would be the used if temporal information has been provided to direct the interception action of hand. This study investigated how the kinematics of interception movement were affected by moving target in different conditions. Three kinds of targets including stationary, uniform motion and accelerated motion were hit by participants. The result reveals that although three tasks are performed within the same time, the hand movements are significantly different. This suggests that in addition to temporal information, spatial information also plays an important role in the motor control during interception.

Predictive Missile Guidance with Online Trajectory Learning

<p>This study presents a predictive guidance scheme for tactical missiles. The modern day targets, with improved manoeuverability, have revealed insufficient performance of the conventional guidance laws. The underlying cause of this poor performance is the reactive nature of the conventional guidance laws such as proportional navigation (PN) and pure pursuit (PP). Predictive guidance offers an alternative approach to the classical methods by taking proactive actions by estimating target’s future trajectory. However, most of the existing predictive guidance approaches assume that the interceptor have a model of the target dynamics. A guidance strategy is developed in this study, that can learn the target dynamics iteratively and adapt the interceptor actions accordingly. A recursive least squares (RLS) estimation algorithm is employed for learning and estimating the possible future target positions, and a fixed horizon nonlinear program is employed for selecting the optimal interception action. Monte-Carlo simulations show that the guidance algorithm introduced in this work demonstrates a significantly improved performance compared to the alternatives in terms of interception time and miss distance.</p>

Temporal and spatial occlusion of advanced visual information constrains movement (re)organization in one-handed catching behaviors

Dynamic interceptive actions are performed under severe spatial and temporal constraints. Here, behavioral processes underpinning anticipation in one-handed catching were examined using novel technology to implement a spatial and temporal occlusion design. Video footage of an actor throwing a ball was manipulated to create four temporal and five spatial occlusion conditions. Data from twelve participants' hand kinematics and gaze behaviors were recorded while attempting to catch a projected ball synchronized with the video footage. Catching performance decreased with earlier occlusion of the footage. Movement onset of the catching hand and initiation of visual ball tracking emerged earlier when footage of the thrower was occluded at a later time point in the throwing action. Spatial occlusion did not affect catching success, although movement onset emerged later when increased visual information of the actor was occluded. Later movement onset was countered by greater maximum velocity of the catching hand. Final stages of action (e.g., grasping action of the hand) remained unchanged across both spatial and temporal conditions suggesting that later phases of the action were organized using ball flight information. Findings highlighted the importance of maintaining information-movement coupling during performance of interceptive actions, since movement behaviors were continuously (re)organized using kinematic information from a thrower's actions and ball flight information.

Expert players accurately detect an opponent's movement intentions through sound alone.

Sounds offer a rich source of information about events taking place in our physical and social environment. However, outside the domains of speech and music, little is known about whether humans can recognize and act upon the intentions of another agent's actions detected through auditory information alone. In this study we assessed whether intention can be inferred from the sound an action makes, and in turn, whether this information can be used to prospectively guide movement. In 2 experiments experienced and novice basketball players had to virtually intercept an attacker by listening to audio recordings of that player's movements. In the first experiment participants had to move a slider, while in the second one their body, to block the perceived passage of the attacker as they would in a real basketball game. Combinations of deceptive and nondeceptive movements were used to see if novice and/or experienced listeners could perceive the attacker's intentions through sound alone. We showed that basketball players were able to more accurately predict final running direction compared to nonplayers, particularly in the second experiment when the interceptive action was more basketball specific. We suggest that athletes present better action anticipation by being able to pick up and use the relevant kinematic features of deceptive movement from event-related sounds alone. This result suggests that action intention can be perceived through the sound a movement makes and that the ability to determine another person's action intention from the information conveyed through sound is honed through practice. (PsycINFO Database Record

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

A SYSTEMATIC REVIEW ON THE EFFECTIVENESS OF PERCEPTUAL MOTOR TRAINING ON IMPROVEMENT IN MOTOR PERFORMANCE IN INDIVIDUALS HAVING DEVELOPMENTAL COORDINATION DISORDER

Purpose: To systematically review published research literatures to identify and evaluate the effectiveness of perceptual motor training on improvement in motor performance in individuals having Developmental Coordination Disorder (DCD).Methods: Multiple databases were methodically searched for articles related to Developmental Coordination Disorder; only descriptive, intervention or qualitative articles were retained. Research indicates that poor motor co-ordination has far reaching implications for social and emotional wellbeing and that DCD occurs not only in children, but that motor difficulties are retained in adulthood.Results: Generalized performance deficit is observed in majority of the children with DCD. Pronounced difficulty in internal (forward) modeling, rhythmic coordination, executive function, gait and postural control, catching and interceptive action, and aspects of sensoriperceptual function were observed in most of the individuals diagnosed with DCD.Conclusions: Result suggests the perceptual motor training approach may result in positive outcomes in motor performance in individuals having DCD. Cognitive orientation to daily occupational performance was observed as better alternative to contemporary coordination treatment approach. Furthermore, psychomotor therapy which includes emphasis on music and rhythm and sensory integration therapy was observed as having sustainably facilitative impacts.

Changes in organisation of instep kicking as a function of wearing compression and textured materials

This study investigated effects of wearing compression garments and textured insoles on modes of movement organisation emerging during performance of lower limb interceptive actions in association football. Participants were six skilled (age = 15.67 ± 0.74 years) and six less-skilled (age = 15.17 ± 1.1 years) football players. All participants performed 20 instep kicks with maximum velocity in four randomly organised insoles and socks conditions, (a) Smooth Socks with Smooth Insoles (SSSI); (b) Smooth Socks with Textured Insoles (SSTI); (c) Compression Socks with Smooth Insoles (CSSI); and (d), Compression Socks with Textured Insoles (CSTI). Results showed that, when wearing textured and compression materials (CSSI condition), less-skilled participants displayed significantly greater hip extension and flexion towards the ball contact phase, indicating larger ranges of motion in the kicking limb than in other conditions. Less-skilled participants also demonstrated greater variability in knee–ankle intralimb (angle–angle plots) coordination modes in the CSTI condition. Findings suggested that use of textured and compression materials increased attunement to somatosensory information from lower limb movement, to regulate performance of dynamic interceptive actions like kicking, especially in less-skilled individuals.

Compression and texture in socks enhance football kicking performance

The purpose of this study was to observe effects of wearing textured insoles and clinical compression socks on organisation of lower limb interceptive actions in developing athletes of different skill levels in association football. Six advanced learners and six completely novice football players (15.4±0.9years) performed 20 instep kicks with maximum velocity, in four randomly organised insoles and socks conditions, (a) Smooth Socks with Smooth Insoles (SSSI); (b) Smooth Socks with Textured Insoles (SSTI); (c) Compression Socks with Smooth Insoles (CSSI) and (d), Compression Socks with Textured Insoles (CSTI). Reflective markers were placed on key anatomical locations and the ball to facilitate three-dimensional (3D) movement recording and analysis. Data on 3D kinematic variables and initial ball velocity were analysed using one-way mixed model ANOVAs. Results revealed that wearing textured and compression materials enhanced performance in key variables, such as the maximum velocity of the instep kick and increased initial ball velocity, among advanced learners compared to the use of non-textured and compression materials. Adding texture to football boot insoles appeared to interact with compression materials to improve kicking performance, captured by these important measures. This improvement in kicking performance is likely to have occurred through enhanced somatosensory system feedback utilised for foot placement and movement organisation of the lower limbs. Data suggested that advanced learners were better at harnessing the augmented feedback information from compression and texture to regulate emerging movement patterns compared to novices.

Cue informativeness constrains visual tracking during an interceptive timing task.

Interceptive actions, such as catching, are a fundamental component of many activities and require knowledge of advanced kinematic information and ball flight characteristics to achieve successful performance. Rather than combining these sources of information, recent exploration of interceptive actions has presented them individually. Thus, it still is unclear how the information available from advanced cues influences eye movement behaviour. By integrating advanced visual information with novel ball projection technology, this study examined how the availability of advanced information, using four different cueing conditions: no image (ball flight only with no advanced information), non-informative (ball flight coupled with ball release information), directional (ball flight coupled with directional information), and kinematic (ball flight coupled with video of a throwing action), influenced visual tracking during a one-handed catching task. The findings illustrated no differences in catching performance across conditions; however, tracking of the ball was initiated earlier, for a longer duration, and over a greater proportion of the ball's trajectory in the directional and kinematic conditions. Significant differences between a directional cue and kinematic cue were not evident, suggesting a simple cue that provided information on the time of release and direction of ball flight was sufficient for successfully anticipating ball release and constraining eye movements. These findings highlight the relationship between advanced information and gaze behaviour during ball flight, and the performance of dynamic interceptive actions. We discuss the implications and potential limitations (e.g. variability between throwing image and ball projection) of the findings in the context of recent research on catching.

Informational constraints on interceptive actions of elite football goalkeepers in 1v1 dyads during competitive performance

ABSTRACTThe aim of this study was to examine whether perceptual variables can provide informational constraints for the goalkeepers to intercept the ball successfully in 1v1 dyads. Video images of 42 actions (1v1 in direct shots) were selected randomly from different matches and divided into conceded goals (n = 20) and saved actions (n = 22) to investigate interceptive actions of 20 goalkeepers in the English Premier League in season 2013–2014. Time to Contact (TTC) of the closing distance gap between shooter and goalkeeper was obtained by digitising actions in the 18-yard penalty box. Statistical analyses revealed that, in sequences of play resulting in an intercepted shot at goal, goalkeepers closed down outfield players in the X axis, whereas when a goal was conceded, there was a significantly delayed movement by goalkeepers toward the shooters in this plane. The results of canonical correlations showed that a decreasing distance between a shooter and goalkeeper, and accompanied reduction in relative interpersonal velocity followed a temporal pattern. Findings of this study showed how perception of key informational constraints on dyadic system relations, such as TTC, interpersonal distance and relative velocity, constrain elite goalkeepers’ interceptive actions, playing an important role in successful performance.

Can we hasten expertise by video simulations? Considerations from an ecological psychology perspective

In their 1994 publication, Starkes and Lindley considered whether perceptual skill could be trained through the observation of video simulations of sport situations. We return to this topic 20 years later and provide a critical review of the subsequent research on perceptual learning in sport. We reflect on the implications from recent empirical evidence, which indicates that perceptual expertise in sport is best captured using experimental methods that allow participants to perceive and act (i.e., produce an interceptive action) against an opponent in real-time. Despite the pertinent implications that these findings have for the training of perceptual skill, until now, a review has not been forthcoming. Specifically, we consider the implications of an ecological approach to perceptual learning for training interventions in sport. We provide a critical review of current literature, before focussing on an ecological theory of learning as a framework for our perspective. We then overview two contemporary topics in ecological psychology - continuum of contact and between-participant variability in perception-action - before considering the implications of our perspective for future research.

Mapping Time-to-Contact and Time-to-Peak Effector Velocity in Interceptive Striking Tasks

Purpose: This study investigated perception and action coupling as reflected in a mapping between time-to-contact (TTC) and time-to-peak-velocity (TPV) for children and youths aged 7 to 8, 11 to 12, and 15 to 16 years old and adults aged 19 to 20 years old performing a task that allowed the participants to self-select the interception position in a baseball-like batting game on a graphics tablet. Method: The moving object to be hit for distance had curvilinear trajectories toward the hitter that were determined by simulated weightings of gravity and velocity. Results: Successful interceptions in all age groups were characterized by a mapping of mean TTC and TPV and a higher correlation of these variables with increasing age. The object was hit at approximately 90% TPV so that the implement was still accelerating on contact—an adaptive task feature for a striking distance criterion. Conclusion: The results are consistent with theories of perception–action coupling that are congruent with the ecological and dynamical approaches to action where TTC, a source of environmental information, is mapped relative to TPV, largely independent of the particular kinematic task demands of the approaching object. The organization of the coupling of TTC prior to TPV was evident across all age groups and is evidence for a common strategy for this type of interceptive action. The age-related changes in the strength of the relationship between TTC and TPV are evidence of increased sensitivity to the coupling between TTC and TPV.

Haptic plus auditory feedback help timing interceptive actions in the absence of late vision.

Haptic plus auditory feedback help timing interceptive actions in the absence of late vision.

Contributions of Visuo-oculomotor Abilities to Interceptive Skills in Sports.

Monitoring and intercepting a fast approaching object is a critical skill for many sports. Athletes might be distinguished from nonathletes based on their ability to access various visual abilities to accomplish interceptive actions. Here, we examined whether interceptive visuomotor skills of athletes and nonathletes are differently correlated to a hierarchy of visuo-oculomotor abilities related to the perception of motion in depth. Eighty-six athletes in interceptive sports, as well as 60 nonathletes, were recruited based on their sport performance and prior experiences. Their basic visual abilities (dominant eye acuity, contrast sensitivity, visual span, and visual memory) and complex visuo-oculomotor abilities (dynamic acuity, accommodative facility, near point of convergence, and near/far phoria) were analyzed in relation to critical visuomotor skills (manual interception, visually guided locomotion, and depth judgment). Discriminant analysis revealed that athletes and nonathletes can be accurately differentiated based on measured visuomotor skills (91.3% accuracy, p < 0.0001). Near point of convergence, accommodative facility, and dynamic acuity were moderately effective in identifying athletes (71.3%, p = 0.002) and in predicting the three visuomotor skills (all r(2) ≥ 0.096, all p ≤ 0.022). Dominant eye acuity and contrast sensitivity also identified athletes (61.4%, p = 0.021) and contributed to complex visuo-oculomotor abilities (all r(2) ≥ 0.046, all p ≤ 0.039). The correlations among measured abilities were more significant for athletes than nonathletes. Athletes in interceptive sports are superior to nonathletes in their visuomotor skills. They also have broader access to various visual and complex visuo-oculomotor abilities than nonathletes. This likely allows athletes to more effectively coordinate visual and oculomotor abilities under demanding conditions when some visual cues are degraded. The present findings are consistent with a pyramid of sports vision and suggest a top-down process for athlete screening and training.

Potential of rapid adjustment of brief interceptive action using predicted information

Interceptive actions, such as hitting a ball in baseball or tennis, feature a moving target whose parameters (i.e., velocity or trajectory) differ across trials. This means that players are required to make rapid trial-by-trial adjustments. The purpose of this study was to determine whether a brief interceptive action could be adjusted using predicted sensory consequence of movement (pSCM) information, even under severe time constraints where the participants could not adjust their movement using only visual feedback.Participants performed an interceptive action for targets with two different velocities with different occurrence probabilities (20%, 50%, and 80%). Prior to movement onset, we applied transcranial magnetic stimulation (TMS) to the supplementary motor area (SMA), as TMS of the SMA is known to disrupt pSCM activity. We hypothesized that if pSCM information were used to adjust the motor parameters of a brief interception, then TMS would significantly increase the constant temporal error (i.e., the difference between the sum of reaction time and movement time and the total target visible time) for a target velocity with a low probability (20%). This hypothesis is based on the previous findings that the pSCM plays an important role in the adjustment of relatively brief interception. We found that while interceptions that lasted about 250ms after movement onset were unaffected, interceptions that lasted about 350ms after movement onset could be influenced by TMS. However, TMS interfered with performance provided that the delivery of the pulse occurred 100ms before movement onset. This finding suggests that pSCM information that is used for a rapid adjustment is generated only in that specific time interval.

Color perception is impaired in baseball batters while performing an interceptive action.

In order to test the theoretical idea that experts rely more on the dorsal stream than the ventral stream during interceptive action for the interception of a moving target, the present study investigates the perception of color (dominant in ventral processing) during interceptive action in fast-ball sports. Twelve college baseball players and 12 non-baseball players performed a coincident-timing task with target color changes (from white to red, blue, or white) at various time points (at 100, 200, or 300 ms before target arrival). In this task, participants swung a bat and/or pressed a button in response to the target's arrival at a prespecified location. Participants were then asked to state the final color of the target. Baseball players, but not non-baseball players, were significantly less proficient at identifying color changes during the bat-swing condition relative to the button-press condition, irrespective of the time points of color change. These results are consistent with the idea that baseball players rely more on the dorsal stream during bat swinging for the interception of a moving target than do novices.

Predictive plus online visual information optimizes temporal precision in interception.

Humans time their interceptive actions with remarkable precision. This daily-life performance is far too good to be explained by reported experimental perceptual estimates of when an object will arrive at the interception location. One option is that people use general principles to reduce variability such as integrating early estimates from predictive mechanisms with late estimates from online vision. Here we explore this possibility by presenting virtual balls that people had to catch and compared 3 conditions: early, late, and full vision of a parabolic path. If people integrate these different estimates, the precision of the timing under full vision should be higher than when only late vision is available. We tested this hypothesis and found a benefit for full vision, but only for those (steeper) trajectories in which early and late estimates are likely based on different cues. Overall, the integration of the different estimates of the impending interceptive event was optimal and can help explain the observed high temporal precision in many daily-life situations. Finally, by revealing the situations in which people do not take into account early predictions and rely on online visual information only we elucidate the theoretical controversy between predictive versus online control of timed actions.