Motor Skills in Children Aged 7–10 Years, Diagnosed with Autism Spectrum Disorder

This study used the Movement Assessment Battery for Children (M-ABC2) to assess the level of motor skill in children aged 7-10 years with autism (n=18) and compared their performance to two groups of age-matched typically developing children; a receptive vocabulary matched group (n=19) and a nonverbal IQ matched group (n=22). Although the results support previous work, as indicated by a significant general motor impairment in the group with autism, a sub-analysis of the M-ABC2 revealed that there were only 2 out of 8 subcomponent skills which showed universally significant specific deficits for the autism group; namely catching a ball and static balance. These results suggest that motor skill deficits associated with autism may not be pervasive but more apparent in activities demanding complex, interceptive actions or core balance ability.

Perceiving and acting upon spaces in a VR rugby task: Expertise effects in affordance detection and task achievement

This study used a virtual simulated 3vs3 rugby task to investigate whether gaps opening in particular running channels promote different actions by the ball-carrier player and whether an effect of rugby expertise is verified. We manipulated emergent gaps in three different locations: gap1 in the participant’s own running channel, gap 2 in the 1st receiver's running channel, and gap3 in the 2nd receiver's running channel. Recreational, intermediate, professional and non-rugby players performed the task. They could i) run with the ball, ii) make a short pass, or iii) make a long pass. All actions were digitally recorded. Results revealed that the emergence of gaps in the defensive line with respect to the participant’s own position significantly influenced action selection. Namely, ‘run’ was most often the action performed in gap 1, ‘short pass’ in gap 2, and ‘long pass’ in gap 3 trials. Furthermore, a strong positive relationship between expertise and task achievement was found.

Expertise is perceived from both sound and body movement in musical performance

Music is a rich form of nonverbal communication, in which the movements that expert musicians make during performance can influence the perception of expressive and structural features of the music. Whether the actual skill of a musician is perceivable from vision of movement was examined. In Experiment 1, musicians and non-musicians rated performances by novice, intermediate and expert clarinettists from point-light animations of their movements, sound recordings, or both. Performances by clarinettists of more advanced skill level were rated significantly higher from vision of movements, although this effect was stronger when sound was also presented. In Experiment 2, movements and sound from the novice and expert clarinettists' performances were switched for half the presentations, and were matched for the rest. Ratings of novice music were significantly higher when presented with expert movements, although the opposite was not found for expert sound presented with novice movements. No perceptual effect of raters' own level of musicianship was found in either experiment. These results suggest that expertise is perceivable from vision of musicians' body movements, although perception of skill from sound is dominant. The results from Experiment 2 further indicate a cross-modal effect of vision and audition on the perception of musical expertise. © 2012 Elsevier B.V.

Ecological impacts of an invasive predator explained and predicted by comparative functional responses

Forecasting the ecological impacts of invasive species is a major challenge that has seen little progress, yet the development of robust predictive approaches is essential as new invasion threats continue to emerge. A common feature of ecologically damaging invaders is their ability to rapidly exploit and deplete resources. We thus hypothesized that the 'functional response' (the relationship between resource density and consumption rate) of such invasive species might be of consistently greater magnitude than those of taxonomically and/or trophically similar native species. Here, we derived functional responses of the predatory Ponto-Caspian freshwater 'bloody red' shrimp, Hemimysis anomala, a recent and ecologically damaging invader in Europe and N. America, in comparison to the local native analogues Mysis salemaai and Mysis diluviana in Ireland and Canada, respectively. This was conducted in a novel set of experiments involving multiple prey species in each geographic location and a prey species that occurs in both regions. The predatory functional responses of the invader were generally higher than those of the comparator native species and this difference was consistent across invaded regions. Moreover, those prey species characterized by the strongest and potentially de-stabilizing Type II functional responses in our laboratory experiments were the same prey species found to be most impacted by H. anomala in the field. The impact potential of H. anomala was further indicated when it exhibited similar or higher attack rates, consistently lower prey handling times and higher maximum feeding rates compared to those of the two Mysis species, formerly known as 'Mysis relicta', which itself has an extensive history of foodweb disruption in lakes to which it has been introduced. Comparative functional responses thus merit further exploration as a methodology for predicting severe community-level impacts of current and future invasive species and could be entered into risk assessment protocols.

Timekeeping strategies operate independently from spatial and accuracy demands in beat-interception movements

The prevailing paradigm for researching sensorimotor synchronisation in humans involves finger tapping and temporal accuracy measures. However, many successful sensorimotor synchronisation actions require not only to be 'in time', but also to be in a predefined spatial position. Reaching this spatial position in many everyday actions often exceeds the average amplitude of a finger movement. The aim of this study is to address how people coordinate their movement to be in the right place at the right time when the scale of the movement varies. Does the scale of the movement and accuracy demands of the movement change the ability to accurately synchronise? To address these questions, a sensorimotor synchronisation task with three different inter-beat intervals, two different movement amplitudes and two different target widths was used. Our experiment demonstrated that people use different timing strategies-employing either a movement strategy (varying movement time) or a waiting strategy (keeping movement time constant) for large-scale movements. Those two strategies were found to be equally successful in terms of temporal accuracy and variability (spread of errors). With longer interval durations (2.5 and 3.5 s), variability of sensorimotor synchronisation performance increased (measured as the spread of errors). Analysing the data using the Vorberg and Wing (Handbook of perception and action. Academic Press, New York, pp 181-262, 1996) model shows a need to develop further existing timing models of sensorimotor synchronisation so that they could apply to large-scale movements, where different movement strategies naturally emerge.

Perceiving and Reenacting Spatiotemporal Characteristics of Walking Sounds

Many studies have examined the processes involved in recognizing types of human action through sound, but little is known about whether the physical characteristics of an action (such as kinetic and kinematic parameters) can be perceived and imitated from sound. Twelve young healthy adults listened to recordings of footsteps on a gravel path taken from walks of different stride lengths (SL) and cadences. In 1 protocol, participants performed a real-time reenactment of the walking action depicted in a sound sample. Second, participants listened to 2 different sound samples and discriminated differences in SL. In a 2nd experiment, these procedures were repeated using synthesized sounds derived from the kinetic interactions between the foot and walking surface. A 3rd experiment examined the influence of altered cadence on participants' ability to discriminate changes in SL. Participants significantly adapted their own SL and cadence according to those depicted in both real and synthesized sounds (p <.01). However, although participants accurately discriminated between large changes in SL, these perceptions were heavily influenced by temporal factors, that is, when cadence changed between samples. These findings show that spatial attributes of action sounds can be both mimicked and discriminated, even when only basic kinetic interactions present within the action are specified. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Detecting Deception in Movement: The Case of the Side-Step in Rugby

Although coordinated patterns of body movement can be used to communicate action intention, they can also be used to deceive. Often known as deceptive movements, these unpredictable patterns of body movement can give a competitive advantage to an attacker when trying to outwit a defender. In this particular study, we immersed novice and expert rugby players in an interactive virtual rugby environment to understand how the dynamics of deceptive body movement influence a defending player’s decisions about how and when to act. When asked to judge final running direction, expert players who were found to tune into prospective tau-based information specified in the dynamics of ‘honest’ movement signals (Centre of Mass), performed significantly better than novices who tuned into the dynamics of ‘deceptive’ movement signals (upper trunk yaw and out-foot placement) (p<.001). These findings were further corroborated in a second experiment where players were able to move as if to intercept or ‘tackle’ the virtual attacker. An analysis of action responses showed that experts waited significantly longer before initiating movement (p<.001). By waiting longer and picking up more information that would inform about future running direction these experts made significantly fewer errors (p<.05). In this paper we not only present a mathematical model that describes how deception in body-based movement is detected, but we also show how perceptual expertise is manifested in action expertise. We conclude that being able to tune into the ‘honest’ information specifying true running action intention gives a strong competitive advantage.

Consensus statements for management of Barrett's dysplasia and early-stage esophageal adenocarcinoma, based on a Delphi process

Esophageal adenocarcinoma (EA) is increasingly common among patients with Barrett's esophagus (BE). We aimed to provide consensus recommendations based on the medical literature that clinicians could use to manage patients with BE and low-grade dysplasia, high-grade dysplasia (HGD), or early-stage EA.

The use of material flow analysis and the ecological footprint in regional policy-making: application and insights from Northern Ireland.

This paper aims to contribute to the ongoing debate on the use of resource accounting tools in regional policy making. The Northern Limits project applied Material Flow Analysis and Ecological Footprinting to regional policy making in Northern Ireland over a number of years. The early phase of the research informed the regions first sustainable development strategy which was published in 2006 with key targets relating to the Ecological Footprint and improving the resource efficiency of the economy. Phase II identified the next steps required to address data availability and quality and the use of MFA and EF in providing a measurement and monitoring framework for the strategy and in the development of the strategy implementation plan. The use of MFA and Ecological Footprinting in sustainable regional policy making and the monitoring of its implementation is an ongoing process which has raised a number of research issues which can inform the ongoing application and development of these and other resource accounting tools to within Northern Ireland, provide insights for their use in other regions and help set out the priorities for research to support this important policy area.

Bending It Like Beckham: How to Visually Fool the Goalkeeper

Background: As bending free-kicks becomes the norm in modern day soccer, implications for goalkeepers have largely been ignored. Although it has been reported that poor sensitivity to visual acceleration makes it harder for expert goalkeepers to perceptually judge where the curved free-kicks will cross the goal line, it is unknown how this affects the goalkeeper's actual movements.

Methodology/Principal Findings: Here, an in-depth analysis of goalkeepers' hand movements in immersive, interactive virtual reality shows that they do not fully account for spin-induced lateral ball acceleration. Hand movements were found to be biased in the direction of initial ball heading, and for curved free-kicks this resulted in biases in a direction opposite to those necessary to save the free-kick. These movement errors result in less time to cover a now greater distance to stop the ball entering the goal. These and other details of the interceptive behaviour are explained using a simple mathematical model which shows how the goalkeeper controls his movements online with respect to the ball's current heading direction. Furthermore our results and model suggest how visual landmarks, such as the goalposts in this instance, may constrain the extent of the movement biases.

Conclusions: While it has previously been shown that humans can internalize the effects of gravitational acceleration, these results show that it is much more difficult for goalkeepers to account for spin-induced visual acceleration, which varies from situation to situation. The limited sensitivity of the human visual system for detecting acceleration, suggests that curved free-kicks are an important goal-scoring opportunity in the game of soccer.

Temporal guidance of musicians’ performance movement is an acquired skill

The ancillary (non-sounding) body movements made by expert musicians during performance have been shown to indicate expressive, emotional, and structural features of the music to observers, even if the sound of the performance is absent. If such ancillary body movements are a component of skilled musical performance, then it should follow that acquiring the temporal control of such movements is a feature of musical skill acquisition. This proposition is tested using measures derived from a theory of temporal guidance of movement, “General Tau Theory” (Lee in Ecol Psychol 10:221–250, 1998; Lee et al. in Exp Brain Res 139:151–159, 2001), to compare movements made during performances of intermediate-level clarinetists before and after learning a new piece of music. Results indicate that the temporal control of ancillary body movements made by participants was stronger in performances after the music had been learned and was closer to the measures of temporal control found for an expert musician’s movements. These findings provide evidence that the temporal control of musicians’ ancillary body movements develops with musical learning. These results have implications for other skillful behaviors and nonverbal communication.

Efficacy of a powered wheelchair simulator for school aged children: A randomised controlled trial.

Purpose: To determine the efficacy of a custom made wheelchair simulation in training children to use a powered wheelchair (PWC). Design: Randomised controlled trial employing the 4C/ID-model of learning. Twenty-eight typically developing children (13M, 15F; mean age 6 years, SD 6 months) were assessed on their operation of a PWC using a functional evaluation rating scale. Participants were randomly assigned to intervention (8x 30minute training sessions using a joystick operated wheelchair simulation) or control conditions (no task), and were re-assessed on their PWC use following the intervention phase. Additional data from the simulation on completion times, errors and total scores were recorded for the intervention group. Results: Analysis of variance showed a main effect of time, with planned comparisons revealing a statistically significant change in PWC use for the intervention (p = 0.022) but not the control condition. Whilst the intervention group showed greater improvement than the controls this did not reach statistical significance. Multiple regression analyses showed that gender was predictive of pre-test (p = 0.005) functional ability. Implications: A simulated wheelchair task appears to be effective in helping children learn to operate a PWC. Greater attention should be given to female learners who underperformed when compared to their male counterparts. This low cost intervention could be easily employed at home to reduce PWC training times in children with motor disorders.