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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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A. Mark Williams and David Elliott

The effects of anxiety and expertise on visual search strategy in karate were examined. Expert and novice karate performers moved in response to taped karate offensive sequences presented under low (LA) and high anxiety (HA). Expert performers exhibited superior anticipation under LA and HA. No differences were observed between groups in number of fixations, mean fixation duration, or total number of fixation locations per trial. Participants displayed scan paths ascending and descending the centerline of the body, with primary fixations on head and chest regions. Participants demonstrated better performance under HA than under LA. Anxiety had a significant effect on search strategy, highlighted by changes in mean fixation duration and an increase in number of fixations and total number of fixation locations per trial. Increased search activity was more pronounced in novices, with fixations moving from central to peripheral body locations. These changes in search strategy with anxiety might be caused by peripheral narrowing or increased susceptibility to peripheral distractors.

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Silvia Varela, José M. Cancela, Manuel Seijo-Martinez, and Carlos Ayán

intervention on the level of attention, visual scanning, and processing speed of the participants were assessed by means of the symbol digit modalities test (SDMT) ( Smith, 2002 ). This test requires individuals to identify nine different symbols corresponding to the numbers 1 through 9 and to practice writing

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Laura Žlibinaitė, Rima Solianik, Daiva Vizbaraitė, Dalia Mickevičienė, and Albertas Skurvydas

time. During the task, the participant must decide whether the letter presented belongs or does not belong to the string. 24 , 25 The code substitution learning task measures visual scanning and associative learning skills. It consists of a code of 9 distinct symbols paired with a single-digit number

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Peter Catteeuw, Bart Gilis, Johan Wagemans, and Werner Helsen

This two-experiment study aims to investigate the role of expertise in offside decision making (Experiment 1) and the effect of perceptual-cognitive training (Experiment 2). In Experiment 1, a video-based offside decision-making task followed by a frame recognition task demonstrated a bias toward flag errors and a forward memory shift for less-successful elite-standard assistant referees that is in line with the predictions from the flash-lag effect. In Experiment 2, an offside decision-making training program demonstrated a substantial progress from pre- to posttest for response accuracy, but not for accuracy of memory in the frame recognition task. In both experiments, no differences were found for visual scan patterns. First, these results suggest that less-successful elite-standard assistant referees are more affected by the flash-lag effect. Second, an off-field perceptual-cognitive training program can help assistant referees to deal with the perceptual consequences of the flash-lag illusion and to readjust their decision-making process accordingly.

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Elizabeth Petrakis

This investigation analyzed the visual search patterns of novice and expert dance teachers when viewing a live performance of a dance composition. The hypotheses tested were that (a) experts would not differ from novices in the number of eye fixations and duration of each, (b) the number of fixations and duration of each would differ between dances, and (c) expert teachers’ search patterns would differ from those of novice teachers. The subjects were four experts who averaged 25.5 years of teaching, and five novice teachers who averaged 2.4 years. To determine the ocular fixation and scanning patterns of subjects, the NAC Eye Movement Recorder, a corneal reflection technique, was used. The films were analyzed using a computer program designed to collect the data. Two 2 × 2 (expertise and dances) analyses of variance were used to determine the differences in the number of fixations, duration of fixations, and differences of variable between dances. Chi-square was used to determine the location of scan patterns. Results indicated that the level of expertise did not influence the number or duration of each eye fixation, but the task being observed did influence these variables. Individual differences in visual scanning patterns were found among and within both groups.

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Bouwien Smits-Engelsman, Wendy Aertssen, and Emmanuel Bonney

that during consecutive trials, recognition of the pattern (via visual scanning) may be needed to induce appropriate decisions to accurately produce motor outputs to complete the task with little or no mistakes ( 10 , 19 , 26 ). Children who can demonstrate effective use of these mechanisms at the

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Carlos Ayán, Paulo Carvalho, Silvia Varela, and José María Cancela

seconds required to complete the task. TMT-A reflects aspects of motor control, motor speed, and visual scanning speed, whereas TMT-B is regarded as a sensitive measure of cognitive flexibility. Two more scores are frequently derived from TMT to reflect cognitive performance: the B/A ratio score, which

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Roy David Samuel, Guy Matzkin, Saar Gal, and Chris Englert

relative to collegiate archers in the initial shooting phase. Moreover, the expert archers showed a more stable and consistent visual scanning pattern under distracting conditions. In addition, an archer must control fine motor movements and also be sufficiently strong to accurately shoot in a repetitive

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Eesha J. Shah, Jia Yi Chow, and Marcus J.C. Lee

disciplines of shooting ( Causer et al., 2010 ; Fegatelli, Giancamilli, Mallia, Chirico, & Lucidi, 2016 ; Janelle et al., 2000 ; Vickers & Williams, 2007 ), but pistol shooting has received comparatively less attention. An analysis of visual scanning patterns of pistol shooters states that “although vision