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Patrice Rougier and Mélanie Garin

To determine the relationship between eye movement and postural control on an undisturbed upright stance maintenance protocol, 15 young, healthy individuals were tested in various conditions. These conditions included imposed blinking patterns and horizontal and vertical saccadic eye movements. The directions taken by the center of pressure (CP) were recorded via a force platform on which the participants remained in an upright position. The CP trajectories were used to estimate, via a low-pass filter, the vertically projected movements of the center of gravity (CGv) and consequently the difference CP-CGv. An analysis of the frequency shows that regular bilateral blinking does not produce a significant change in postural control. In contrast, performing saccadic eye movements induces some reduced amplitude for both basic CGv and CP-CGv movements principally along the antero-posterior axis. The present result supports the theory that some ocular movements may modify postural control in the maintenance of the upright standing position in human participants.

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Ali S. Tejani, Bert B. Vargas, Emily F. Middleton and Mu Huang

Key Points ▸ An athlete’s sport may influence efficiency of eye movements. ▸ Sport-specific differences hinders comparison of postconcussion changes to generic baseline eye movements. ▸ Uniformity in contrast acuity may preclude the need for athlete-specific testing. Although numerous studies have

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André Roca, Paul R. Ford, Allistair P. McRobert and A. Mark Williams

The ability to anticipate and to make decisions is crucial to skilled performance in many sports. We examined the role of and interaction between the different perceptual-cognitive skills underlying anticipation and decision making. Skilled and less skilled players interacted as defenders with life-size film sequences of 11 versus 11 soccer situations. Participants were presented with task conditions in which the ball was located in the offensive or defensive half of the pitch (far vs. near conditions). Participants’ eye movements and verbal reports of thinking were recorded across two experiments. Skilled players reported more accurate anticipation and decision making than less skilled players, with their superior performance being underpinned by differences in task-specific search behaviors and thought processes. The perceptual-cognitive skills underpinning superior anticipation and decision making were shown to differ in importance across the two task constraints. Findings have significant implications for those interested in capturing and enhancing perceptual-cognitive skill in sport and other domains.

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Peter Catteeuw, Werner Helsen, Bart Gilis, Evelien Van Roie and Johan Wagemans

The offside decision-making process of international and national assistant referees (ARs) was evaluated using video simulations. A Tobii T120 Eye Tracker was used to record the eye movements. Two hypotheses for explaining incorrect decisions were investigated, namely, the flash-lag effect and the shift of gaze. Performance differences between skill levels were also examined. First, results showed a bias toward flag errors for national ARs as expected by the flash-lag effect. Second, ARs fixated the offside line before, during, and after the precise moment the pass was given, implying there was no shift of gaze from the passer to the receiving attacker. Third, no differences were found in scan patterns between international and national ARs. In conclusion, international ARs seem to have found a strategy to better deal with the perceptual illusion resulting from the flash-lag effect. Based on their experience, they have learned to correct for this illusion, and, consequently, show fewer flag errors.

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Francesc Llorens, Daniel Sanabria, Florentino Huertas, Enrique Molina and Simon Bennett

The abrupt onset of a visual stimulus typically results in overt attentional capture, which can be quantified by saccadic eye movements. Here, we tested whether attentional capture following onset of task-irrelevant visual stimuli (new object) is reduced after a bout of intense physical exercise. A group of participants performed a visual search task in two different activity conditions: rest, without any prior effort, and effort, immediately after an acute bout of intense exercise. The results showed that participants exhibited (1) slower reaction time of the first saccade toward the target when a new object was simultaneously presented in the visual field, but only in the rest activity condition, and (2) more saccades to the new object in the rest activity condition than in the effort activity condition. We suggest that immediately after an acute bout of effort, participants improved their ability to inhibit irrelevant (distracting) stimuli.

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Florian Van Halewyck, Ann Lavrysen, Oron Levin, Digby Elliott and Werner F. Helsen

Older adults traditionally adapt their discrete aiming movements, thereby traveling a larger proportion of the movement under closed-loop control. As the beneficial impact of a physically active lifestyle in older age has been described for several aspects of motor control, we compared the aiming performance of young controls to active and sedentary older adults. To additionally determine the contribution of visual feedback, aiming movements were executed with and without saccades. Results showed only sedentary older adults adopted the typical movement changes, highlighting the impact of a physically active lifestyle on manual aiming in older age. In an attempt to reveal the mechanism underlying the movement changes, evidence for an age-related decline in force control was found, which in turn resulted in an adapted aiming strategy. Finally, prohibiting saccades did not affect older adults’ performance to a greater extent, suggesting they do not rely more on visual feedback than young controls.

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Raoul Huys, Andreas Daffertshofer and Peter J. Beek

To study the acquisition of perceptual-motor skills as an instance of dynamic pattern formation, we examined the evolution of postural sway and eye and head movements in relation to changes in performance, while 13 novices practiced 3-ball cascade juggling for 9 weeks. Ball trajectories, postural sway, and eye and head movements were recorded repeatedly. Performance improved exponentially, both in terms of the number of consecutive throws and the degree of frequency and phase locking between the ball trajectories. These aspects of performance evolved at different time scales, indicating the presence of a temporal hierarchy in learning. Postural sway, and eye and head movements were often 3:2 and sometimes 3:1 frequency locked to the ball trajectories. As a rule, the amplitudes of these oscillatory processes decreased exponentially at rates similar to that of the increase in the degree of phase locking between the balls. In contrast, the coordination between these oscillatory processes evolved exponentially at different time scales, apart from some erratic evolutions. Collectively, these findings indicate that skill acquisition in the perceptual-motor domain involves multiple time scales and multiform dynamics, both in terms of the development of the goal behavior itself and the evolution of the processes subserving this goal behavior.

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Wojciech Jedziniak, Piotr Lesiakowski and Teresa Zwierko

strong evidence to suggest that eye movements are important in this process ( Laurens et al., 2010 ; Rodrigues et al., 2015 ; Thomas, Bampouras, Donovan, & Dewhurst, 2016 ). Saccades are conjugate eye movements that are responsible for the rapid shifts that bring new areas of the visual field into

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Nicholas E. Fears and Jeffrey J. Lockman

use vision during manual tasks can be directly studied with eye-tracking technology. Eye-tracking technology has been used to examine how individuals deployed eye movements as they planned and guided ongoing manual actions during everyday activities ( Gowen & Miall, 2006 ; Hayhoe, 2000 ; Hayhoe

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Erin Berenbaum and Amy E. Latimer-Cheung

Gain-framed messages are more effective at promoting physical activity than loss-framed messages. However, the mechanism through which this effect occurs is unclear. The current experiment examined the effects of message framing on variables described in the communication behavior change model (McGuire, 1989), as well as the mediating effects of these variables on the message-frame–behavior relationship. Sixty low-to-moderately active women viewed 20 gain- or loss-framed ads and five control ads while their eye movements were recorded via eye tracking. The gain-framed ads attracted greater attention, ps < .05; produced more positive attitudes, p = .06; were better recalled, p < .001; influenced decisions to be active, p = .07; and had an immediate and delayed impact on behavior, ps < .05, compared with the loss-framed messages. Mediation analyses failed to reveal any significant effects. This study demonstrates the effects of framed messages on several outcomes; however, the mechanisms underlying these effects remain unclear.