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Cholinergic degeneration is a key feature of dementia in neurodegenerative conditions including Alzheimer's disease (AD) and Parkinson's disease (PD). Quantitative electro-encephalography (EEG) metrics are altered in both conditions from early stages, and recent research in people with Lewy body and AD dementia suggests these changes may be associated with atrophy in cholinergic basal forebrain nuclei (cBF). To determine if these relationships exist in predementia stages of neurodegenerative conditions, we studied resting-state EEG and in vivo cBF volumes in 31 people with PD (without dementia), 21 people with mild cognitive impairment (MCI), and 21 age-matched controls. People with PD showed increased power in slower frequencies and reduced alpha reactivity compared to controls. Volumes of cholinergic cell clusters corresponding to the medial septum and vertical and horizontal limb of the diagonal band, and the posterior nucleus basalis of Meynert, correlated positively with; alpha reactivity in people with PD (p< 0.01); and pre-alpha power in people with MCI (p< 0.05). These results suggest that alpha reactivity and pre-alpha power are related to changes in cBF volumes in MCI and PD without dementia.

[Background] There is an urgent need to identify individuals at risk of postural instability and gait difficulties, and the resulting propensity for falls, in Parkinson's disease., [Objectives] Given known relationships between posture and gait and degeneration of the cholinergic pedunculopontine nucleus, we investigated whether metrics of pedunculopontine nucleus microstructural integrity hold independent utility for predicting future postural instability and gait difficulties and whether they could be combined with other candidate biomarkers to improve prognostication of these symptoms., [Methods] We used stereotactic mapping of the pedunculopontine nucleus and diffusion tensor imaging to extract baseline pedunculopontine nucleus diffusivity metrics in 147 participants with Parkinson's disease and 65 controls enrolled in the Parkinson's Progression Markers Initiative. We also recorded known candidate markers of posture and gait changes: loss of caudate dopamine and CSF β‐amyloid 1‐42 levels at baseline; as well as longitudinal progression motor symptoms over 72‐months., [Results] Survival analyses revealed that reduced dopamine in the caudate and increased axial diffusivity in the pedunculopontine nucleus incurred independent risk of postural instability and gait difficulties. Binary logistic regression and receiver operating characteristics analysis in 117 participants with complete follow‐up data at 60 months revealed that only pedunculopontine nucleus microstructure provided more accurate discriminative ability for predicting future postural instability and gait difficulties than clinical and demographic variables alone., [Conclusion] Dopaminergic and cholinergic loss incur independent risk for future postural instability and gait difficulties, and pedunculopontine nucleus microstructure can be used to prognosticate these symptoms from early Parkinson's disease stages. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society., The Parkinson's Progression Markers Initiative is sponsored and partially funded by the Michael J. Fox Foundation for Parkinson's Research. Other funding partners include a consortium of industry players, nonprofit organizations, and private individuals. Additional funding to support the current analysis was provided by the Wellcome Trust.

BACKGROUND:Sensitivity-related trait characteristics involving physical and emotional sensitivities and high trait anxiety personality types have been observed in individuals with non-specific chronic low back pain (NSCLBP). High trait sensitivity to sensory stimulation combined with interpretation biases based on personality type may contribute to the development of central sensitisation (CS) symptoms. To date there is limited research that has considered both sensitivity levels and personality type in NSCLBP with CS. The purpose of this study was to investigate 1) relationships between trait sensory profiles, trait anxiety and CS symptoms, and 2) the predictive capacity of sensory profiles, trait anxiety and personality types on CS symptoms, in people with NSCLBP. METHODS:This was a cross-sectional observational study using four self-report measures on adults (N = 165, mean age = 45 +-12 SD) from physiotherapy clinics in England, Ireland and New Zealand. Inclusion: NSCLBP > 6 months, aged 18-64, predominant CS pain presentation, no other pathology. Parametric and non-parametric correlation statistics and regression analyses were used. RESULTS:Positive correlations were found between central sensitisation inventory (CSI) scores and sensory hyper-sensitivity profiles and trait anxiety. CSI score increases could be predicted by: Sensory Sensitive, Low Registration profiles, trait anxiety scores and extreme defensive high anxious personality type. CONCLUSIONS:Trait sensory hyper- and/or hypo-sensitivity and high trait-anxiety related personality type characteristics predicts the extent of CS symptoms in people with NSCLBP. Further investigation is required to establish causality between these characteristics and CS symptoms. This article is protected by copyright. All rights reserved.

Action observation has been suggested to be an effective adjunct to physical practice in motor (re)learning settings. However, optimal viewing conditions for interventions are yet to be established. Single-pulse transcranial magnetic stimulation (TMS) was used to investigate the effect of two different screen positions and participants’ screen position viewing preference on the amplitude of motor evoked potentials (MEPs) during observation of a ball pinch action. Twenty-four participants observed four blocked conditions that contained either a dynamic index finger-thumb ball pinch or a static hand holding a ball in a similar position on a horizontally or vertically positioned screen. TMS was delivered to the hand representation of the left primary motor cortex and MEPs were recorded from the first dorsal interosseous muscle of the right hand. Initial analysis of the normalized MEP amplitude data showed no significant differences between conditions. In a follow-up procedure, participants engaged in individual semi-structured interviews and completed a questionnaire designed to assess viewing affect and screen position viewing preference. The MEP data were subsequently split by screen position preference and re-analyzed using a 2 × 2 repeated measures ANOVA. Main effects indicated that participants who preferred the horizontal screen position (n = 16) demonstrated significantly greater MEP amplitudes during observation of the ball-pinch action compared to the static hand condition irrespective of screen position, and during the horizontal compared to the vertical screen position irrespective of video type. These results suggest that ensuring anatomical and perceptual congruency with the physical task, alongside consideration of participants’ screen position viewing preferences, may be an important part of optimizing action observation interventions.

Full trunk control in sitting is demonstrated only when the head-trunk are aligned and upper limbs remain free of contact from mechanical support. These components represent a Controlled Kinetic Chain and can be evaluated in people with neuromotor disability using the Segmental Assessment of Trunk Control (SATCo) when a therapist provides manual trunk support at different segmental levels. However, the SATCo, as with other clinical assessments of control, is subjective. The SATCo was translated to objective rules relating the position of the hands and elbows to the head-trunk and then tested to determine the extent to which this automated objective method replicated the clinical judgement. Clinical evaluation used video to determine whether the upper limb was free of mechanical support while the objective evaluation used 3D motion capture of the trunk and upper limbs with a classification rule. The agreement between clinical and objective classification was calculated for three conditions of a distance-from-support-surface threshold parameter in five healthy adults and five children with cerebral palsy. The unfitted (zero-threshold values) method replicated the clinical judgement in part (68.26%±15.7, adults, 48.3%±33.9 children). The fitted (level-of-support determined) agreement showed that the process could be refined using trial specific parameters (88.32%±5.3 adults, 89.84%±10.2 children). The fixed-values agreement showed high values when using general group parameters (80.80%±3.1 adults, 74.31%±21.5 children). This objective classification of the upper limb component of trunk control largely captures the clinical evaluation. It provides the first stages in development of a clinically-friendly fully automated method.

Motor imagery (MI) and action observation (AO) have traditionally been viewed as two separate techniques, which can both be used alongside physical practice to enhance motor learning and rehabilitation. Their independent use has largely been shown to be effective, and there is clear evidence that the two processes can elicit similar activity in the motor system. Building on these well-established findings, research has now turned to investigate the effects of their combined use. In this article, we first review the available neurophysiological and behavioral evidence for the effects of combined action observation and motor imagery (AO+MI) on motor processes. We next describe a conceptual framework for their combined use, and then discuss several areas for future research into AO+MI processes. In this review, we advocate a more integrated approach to AO+MI techniques than has previously been adopted by movement scientists and practitioners alike. We hope that this early review of an emergent body of research, along with a related set of research questions, can inspire new work in this area. We are optimistic that future research will further confirm if, how, and when this combined approach to AO+MI can be more effective in motor learning and rehabilitation settings, relative to the more traditional application of MI or AO independently.

Attentional biases reflect an individual's selective attention to salient stimuli within their environment, for example an experience of back pain. Eysenck suggests that different personality types show different attentional biases to threatening information. This study is the first to test Eysenck's theory within a chronic back pain population by investigating the attentional biases of four different personality types using a back pain specific dot-probe paradigm. Participants were 70 volunteers (45 female) recruited from a back rehabilitation program at an NHS Trust. The four groups were selected on their trait anxiety and defensiveness scores: defensive high-anxious; high-anxious; repressor and non-extreme. Participants completed a dot probe task comprising 20 practice trials and 250 experimental trials. The experimental trials contained 100 threat-neutral pairs, 100 positive-neutral pairs and 50 neutral-neutral image pairings. The threat images were taken from the Photograph Series of Daily Activities (PHODA) and the neutral and positive images from the International Affective Picture System (IAPS) image bank. The results provided partial support for Eysenck's theory; defensive high-anxious individuals showed an attentional bias for threatening information compared to high-anxious individuals who demonstrated no bias. Repressors showed an avoidant bias to threatening images and an attentional bias to positive stimuli relative to neutral images. The clear difference in responses demonstrated by high-anxious individuals who vary in defensiveness highlight the need for separate investigation of these heterogeneous groups and help to explain the cognitive processes of defensive high-anxious individuals within a pain population. The demonstration of an attentional bias in this group to threatening information could explain why defensive high-anxious individuals are more likely to re-present for treatment.

Motor imagery, or the mental rehearsal of actions in the absence of physical movement, is an increasingly popular construct in fields such as neuroscience, cognitive psychology and sport psychology. Unfortunately, few models of motor imagery have been postulated to date. Nevertheless, based on the hypothesis of functional equivalence between imagery, perception and motor execution, Holmes and Collins in 2001 developed the PETTLEP model of motor imagery in an effort to provide evidence-based guidelines for imagery practice in sport psychology. Given recent advances in theoretical understanding of functional equivalence, however, it is important to provide a contemporary critical reflection on motor imagery research conducted using this model. The present article addresses this objective. We begin by explaining the background to the development of the PETTLEP model. Next, we evaluate key issues and findings in PETTLEP-inspired research. Finally, we offer suggestions for, and new directions in, research in this field. Author has checked copyright kpw13/5/13

To date, no research has investigated score predictions and anxiety interpretation in high-anxious, low-anxious, defensive high-anxious and repressor individuals. This study examined Eysenck’s (1997) predictions for cognitive biases on future performance expectations in all four groups. This study was conducted in an ecologically-valid sporting environment. Competitive shooters completed the Marlowe–Crowne Social Desirability Scale and the Sport Anxiety Scale prior to a major competition. Percentile splits identified the four defensiveness/anxiety groups. The modified Competitive Sport Anxiety Inventory-2 was used to assess the intensity and direction of anxiety prior to competition. Participants predicted their expected shooting score. The hypothesis that repressors would interpret their anxiety as more facilitative to performance compared to low-anxious individuals was partially supported. Repressors were more optimistic in their performance prediction in contrast to defensive high-anxious performers who, in turn, were more pessimistic compared to the other two groupings. High-anxious performers, contrary to predictions, demonstrated optimism in their future performance. The findings of this study corroborate the theoretical predictions and the evidence from previous studies with sport performers. Future research should continue to investigate the influence of cognitive biases on performance predictions in sporting environments using Weinberger et al.’s classifications.

Imagery can improve sport performance, although its efficacy is mediated by the ease with which athletes can generate images. Establishing techniques that improve this imagery ability factor is desirable to enhance the effectiveness of imagery interventions. Twenty-seven club-level female golfers were assigned to imagery, action observation, or physical practice training groups (n = 9). Changes in image generation ease were assessed using the Revised Movement Imagery Questionnaire over an 8-week period. Imagery and action observation training were both effective in improving aspects of imagery ability. Action observation can provide sport psychologists with an effective tool for improving visual imagery ability in athletes.

Observation and imagery of movement both activate similar brain regions to those involved in movement execution. As such, both are recommended as techniques for aiding the recovery of motor function following stroke. Traditionally, action observation and movement imagery have been considered as independent intervention techniques. Researchers have however begun to consider the possibility of combining the two techniques into a single intervention strategy. This study investigated the effect of combined action observation and movement imagery on corticospinal excitability in comparison to either observation or imagery alone. Single-pulse transcranial magnetic stimulation was delivered to the hand representation of the left motor cortex during combined action observation and movement imagery, passive observation, or movement imagery of right index finger abduction-adduction movements or control conditions. Motor evoked potential (MEPs) were recorded from the first dorsal interosseous (FDI) and abductor digiti minimi (ADM) muscles of the right hand. The combined action observation and movement imagery condition produced MEPs of larger amplitude than were obtained during passive observation and control conditions. This effect was only present in the FDI muscle, indicating the facilitation of corticospinal excitability during the combined condition was specific to the muscles involved in the observed/imagined task. These findings have implications for stroke rehabilitation, where combined action observation and movement imagery interventions may prove to be more effective than observation or imagery alone.

Patients with low back pain often demonstrate elevated paraspinal muscle activity compared to asymptomatic controls. This hyperactivity has been associated with a delayed rate of stature recovery following spinal loading tasks. The aim of this study was to investigate the changes in muscle activity and stature recovery in patients with chronic low back pain following an active rehabilitation programme. The body height recovery over a 40-min unloading period was assessed via stadiometry and surface electromyograms were recorded from the paraspinal muscles during standing. The measurements were repeated after patients had attended the rehabilitation programme and again at a six-month follow-up. Analysis was based on 17 patients who completed the post-treatment analysis and 12 of these who also participated in the follow-up. By the end of the six months, patients recovered significantly more height during the unloading session than at their initial visit (ES = 1.18; P < 0.01). Greater stature recovery immediately following the programme was associated with decreased pain (r = -0.55; P = 0.01). The increased height gain after six months suggests that delayed rates of recovery are not primarily caused by disc degeneration. Muscle activity did not decrease after treatment, perhaps reflecting a period of adaptation or altered patterns of motor control.

Transcranial magnetic stimulation (TMS) studies indicate that the observation of other people's actions influences the excitability of the observer's motor system. Motor evoked potential (MEP) amplitudes typically increase in muscles which would be active during the execution of the observed action. This 'motor resonance' effect is thought to result from activity in mirror neuron regions, which enhance the excitability of the primary motor cortex (M1) via cortico-cortical pathways. The importance of TMS intensity has not yet been recognised in this area of research. Low-intensity TMS predominately activates corticospinal neurons indirectly, whereas high-intensity TMS can directly activate corticospinal axons. This indicates that motor resonance effects should be more prominent when using low-intensity TMS. A related issue is that TMS is typically applied over a single optimal scalp position (OSP) to simultaneously elicit MEPs from several muscles. Whether this confounds results, due to differences in the manner that TMS activates spatially separate cortical representations, has not yet been explored. In the current study, MEP amplitudes, resulting from single-pulse TMS applied over M1, were recorded from the first dorsal interosseous (FDI) and abductor digiti minimi (ADM) muscles during the observation of simple finger abductions. We tested if the TMS intensity (110% vs. 130% resting motor threshold) or stimulating position (FDI-OSP vs. ADM-OSP) influenced the magnitude of the motor resonance effects. Results showed that the MEP facilitation recorded in the FDI muscle during the observation of index-finger abductions was only detected using low-intensity TMS. In contrast, changes in the OSP had a negligible effect on the presence of motor resonance effects in either the FDI or ADM muscles. These findings support the hypothesis that MN activity enhances M1 excitability via cortico-cortical pathways and highlight a methodological framework by which the neural underpinnings of action observation can be further explored.

We tested the predictions of Attentional Control Theory (ACT) by examining the effect of anxiety on attention control and the subsequent influence on both performance effectiveness and performance efficiency within a perceptual-motor context. A sample (N = 16) of elite shotgun shooters was tested under counterbalanced low (practice) and high (competition) anxiety conditions. A head-mounted, corneal reflection system allowed point of gaze to be calculated in relation to the scene, while motion of the gun was evaluated using markers placed on the barrel which were captured by two stationary cameras and analyzed using optical tracking software. The quiet eye (QE) duration and onset were analyzed along with gun barrel displacement and variability; performance outcome scores (successful vs. unsuccessful) were also recorded. QE (Vickers, 1996) is defined as the final fixation or tracking gaze that is located on a specific location/object in the visual display for a minimum of 100 ms. Longer QE durations have been linked to successful performance in previous research involving aiming tasks. Participants demonstrated shorter quiet eye durations, and less efficient gun motion, along with a decreased performance outcome (fewer successful trials) under high compared with low anxiety conditions. The data support the predictions of ACT with anxiety disrupting control processes such that goal-directed attention was compromised, leading to a significant impairment in performance effectiveness.

Sport and exercise psychologists provide some interventions for clients based on limited direct evidence and partial understanding of the mechanisms that underpin their efficacy. The authors review a recent technique, transcranial magnetic stimulation (TMS), which offers a tested procedure for investigating cortical activity during observation and imagery processes. They provide a detailed description of the TMS protocol and highlight some of the key studies that inform sport and exercise psychology research. Finally, the authors offer some thoughts on the direct application to practice.

In the last decade, collective efficacy has received increasing attention in the sport psychology literature. However, despite considerable focus on the antecedents and consequences of the construct (e.g., Magyar, Feltz, & Simpson, 2004), no research has considered the specific neuropsychological mechanisms that underpin the levels of collective efficacy perceived by individuals within sports teams. In this respect, neuroscience research outside sport psychology has identified cortical structures linked to socio-cognitive thought processes (e.g., Gallese, Keysers, & Rizzolati, 2004). Therefore, the purpose of this review is to provide evidence for potential neurological processes that underpin collective efficacy perceptions. Specifically, we discuss these processes in relation to how collective efficacy is conceptualized, measured, and analyzed. We then discuss pertinent neuroscience research that indicates both imagery and observation based interventions are suitable for increasing individual collective efficacy perceptions. Finally, based on the neuroscience mechanisms discussed, future directions for research are suggested that aim to increase our understanding of the nature and influence of collective efficacy perceptions upon individual and team behavior.

International audience; Imagery and observation are multicomponential, involving individual difference characteristics that modify the processes. The authors propose that both imagery and observation function by offering effective routes to access and reinforce neural networks for skilled performance. The neural isomor-phism with overt behaviors offers a tempting mechanism to explain the beneficial outcomes of the 2 processes. However, several limitations related to imagery indicate the possibility that imagery may not be as efficacious as the literature would indicate. The authors propose observation-based approaches to offer more valid and effective techniques in sport psychology and motor control.

International audience; The main aim of this study was to examine the temporal aspects of neuronal changes during the observation and execution of simple and complex tasks to gain a greater understanding of the mirror neuron system's involvement in complex motor tasks. Eleven right-handed subjects observed simple and complex Wnger movement sequences. Electroencephalograms were recorded from 19 electrodes. Activity was considered in four frequency bands (8–10, 10–13, 13–20, and 20–30 Hz) using a new measure, synchronization likelihood. The results show that motor tasks of diVerent levels of complexity did not have a signiW-cant inXuence on cortical synchronization. The results also provide additional indirect evidence for mirror neuron activity associated with intransitive tasks. Data are discussed in the light of recent Wndings from the cognitive and behavioral neuroscience literature.

Imagery has been recommended increasingly for use in rehabilitation programs for individuals following a stroke. Frequently, this use is based on the premise that imagery is associated with neural activity in the brain similar to that occurring during the overt behavior and that this isomorphism will benefit the individual. There is evidence that imagery does share neural correlates with the perceptual behavior. However, to optimize and to make functional use of the equivalence, a number of factors need to be considered. Because many of these factors have been omitted from previous research designs, it may be premature to make claims for the success of imagery in the context of stroke rehabilitation. An observation-based approach is proposed to address some of the concerns.

The aim of this study was to test the validity of mirror neuron activity in humans through analysis of electroencephalographic (EEG) functional connectivity during an action not directed towards an object. We investigated changes in EEG interchannel synchronization prior to and during action execution and also prior to and during observation of the same action. Twelve participants observed a simple finger movement sequence. In a second testing session they physically executed the movement. EEGs were recorded from 19 active sites across the cortex. Activity was considered in four frequency bands (7–10 Hz, 10–13 Hz, 13–20 Hz, and 20–30 Hz) using a new measure: synchronization likelihood. This technique considers rapid changes in signal synchronization and spatiotemporal patterns of coherence. The results revealed no statistically significant difference in synchronization likelihood between the observation and execution data. We found an increase in synchronization over a broad frequency range during task processing and suggest that this may reflect interregional cortical coupling of intricately and hierarchically interconnected networks that are active in a similar way during both observation and execution of a movement. While EEG may be insensitive to differences present during the observation and execution of a movement, the results of the present study shed some light on the general mechanisms of cognitive integration. Hum Brain Mapp 27:251–266, 2006. © 2005 Wiley-Liss, Inc.

International audience; The purpose of this study was to examine the variability in cortical activation during physical air-rifle shooting and threedifferent observation conditions. Elite air-rifle shooters performed a 40 shot individual match. Electroencephalograms wererecorded from 11 active sites across the cortex during the final 6 s (362 s epochs) before shot release. Data collection wasrepeated while shooters watched a large-screen video of their worst shot performance from an internal-visual perspectivewhen seated, standing and standing holding their rifle. The hypothesized differences between the three observationconditions and the physical shooting profile were not shown except at the left anterior temporal site, T5. This findingsuggests that observation of performance cannot be differentiated clearly by posture or modified through kinetic and hapticafference, and that visual percepts predominate in observational functional equivalence. However, more functionallyequivalent observation reduced the observation/execution variability over the temporal areas. Performer debriefs alsoidentified different perceptions of physiological, psychological and behavioural functional equivalence associated with thedifferent observation conditions. We conclude that elite performers’ brains are accessed equally effectively during differentobservation conditions irrespective of some of the physical factors ascribed to the conditions. However, they may requiremore functionally matched conditions to attain greater equivalence in temporal areas.

This study examined whether the tendency to interpret anxiety symptoms as facilitative was more a characteristic of individuals classified as repressors than high-anxious and low-anxious sports performers. The influence of the cognitive biases of high-anxious and repressor individuals on future performance expectations was also examined. The state anxiety levels, directional interpretation of anxiety and performance expectations of golfers classified as high-anxious, low-anxious and repressors were examined prior to competition. Performance expectations were compared to actual performances achieved. The proposal that repressors would interpret anxiety symptoms as more facilitative than high-anxious and low-anxious individuals was not supported. Repressors were found to be overly optimistic regarding future performance, consistently predicting better performance than they achieved. Contrary to predictions, performance expectations of the high-anxious group did not differ from those actually achieved. Thus, the proposal that high-anxious individuals would be overly pessimistic was not supported. These findings are discussed within the theory of trait anxiety proposed by Eysenck (1997).

Several years ago Collins and Hale (1997) commented on nonrigorous experimental designs and procedures which typified published research examining the psychophysiology of the imagery process. Conceptual, methodological, and analytical guidelines were offered to improve the quality of future research undertakings. While Slade, Landers, and Martin (2002) have followed some of these suggestions, their recent imagery study examining the “mirror hypothesis” and a theory-expectancy hypothesis with EMG recordings still appears to have some conceptual inconsistencies, methodological flaws, and analytical weaknesses that make their conclusions ambiguous. These concerns are identified, and more suggestions for improved designs are given, in another attempt to improve the quality of the scientific research undertaken in sport psychophysiology.

This investigation examined the predictions of psychoneuromuscular theory (Richardson, 1967) and the effectiveness of mental practice (MP) in enhancing strength performance, using a finger strength task. Eighteen males were randomly assigned to a physical practice (PP) group, a mental practice (MP) group or a control group. PP and MP participants performed two PP or MP sessions per week for four weeks, each session comprising twenty real or imagined maximal contractions of the abductor digiti minimi. There were no significant differences in pre-test abduction force, but post-test scores of the PP and MP groups were significantly greater than those of control participants. Electromyographic (EMG) recordings revealed significant muscle activity during MP, but its magnitude was not significantly correlated with the degree of performance enhancement. Findings therefore supported the effectiveness of MP in enhancing strength performance, but were not supportive of psychoneuromuscular theory.

Introduction: Several researchers have reported the importance of maintaining a longer final fixation on the target (termed the quiet eye period, QE) before performing an aiming task. We present an innovative, perceptual training intervention intended to improve the efficiency of gaze behavior (i.e., QE) in shotgun shooting. Methods: A sample of 20 international-level skeet shooters were assigned equally to one of two ability-matched groups based on their pretest shooting scores. A perceptual training group participated in a four-step preshot routine alongside three video feedback sessions involving their own gaze behaviors and those of an expert model in an effort to positively influence QE behaviors. A control group received video feedback of performance but without the addition of feedback on QE behaviors. Participants completed pretests and posttests along with an 8-wk training intervention. Results: Subjects of the perceptual training group significantly increased their mean QE duration (397 vs 423 ms), used an earlier onset of QE (257 vs 244 ms), and recorded higher shooting accuracy scores (62 vs 70%) from pretest to posttest. Participants in the perceptual training group significantly reduced gun barrel displacement and absolute peak velocity on the posttest compared with the pretest, although neither variable was overtly trained. A transfer test based on performance during competition indicated that perceptual training significantly improved shooting accuracy from before to after the intervention. No pretest to posttest differences were observed for the control group on the measures reported. Conclusions: The results demonstrate the effectiveness of QE training in improving shooting accuracy and developing a more efficient visuomotor control strategy.The findings have implications for future research on training visuomotor behaviors, attention, and gaze orientation during the performance of aiming tasks.

The aim of this paper is to provide a review of eye movements during action execution, action observation, and movement imagery. Furthermore, the paper highlights aspects of congruency in gaze metrics between these states. The implications of the imagery, observation, and action gaze congruency are discussed in terms of motor learning and rehabilitation. Future research directions are outlined in order to further the understanding of shared gaze metrics between overt and covert states. Suggestions are made for how researchers and practitioners can structure action observation and movement imagery interventions to maximize (re)learning.

INTRODUCTION:\ud No literature exists to document skill-related differences in shotgun shooting and whether these may be a function of eye movements and control of gun motion. We therefore conducted an exploratory investigation of the visual search behaviors and gun barrel kinematics used by elite and subelite shooters across the three shotgun shooting subdisciplines.\ud METHODS:\ud Point of gaze and gun barrel kinematics were recorded in groups of elite (n = 24) and subelite (n = 24) shooters participating in skeet, trap, and double trap events. Point of gaze was calculated in relation to the scene, while motion of the gun was captured by two stationary external cameras. Quiet eye (final fixation or tracking gaze that is located on a specific location/object in the visual display for a minimum of 100 ms) duration and onset were analyzed as well as gun motion profiles in the horizontal and vertical planes.\ud RESULTS:\ud In skeet, trap, and double trap disciplines, elite shooters demonstrated both an earlier onset and a longer relative duration of quiet eye than their subelite counterparts did. Also, in all three disciplines, quiet eye duration was longer and onset earlier during successful compared with unsuccessful trials for elite and subelite shooters. Kinematic analyses indicated that a slower movement of the gun barrel was used by elite compared with subelite shooters.\ud CONCLUSIONS:\ud Overall, stable gun motion and a longer quiet eye duration seem critical to a successful performance in all three shotgun disciplines.