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ABSTRACTThis study novelty aimed to investigate the influence of manipulating the available time to perform the training tasks on soccer players´ ocular metrics, following training. Specifically, pupillary response (pupil diameter) and saccadic features (latency, accuracy, velocity, and number) were measured with a portable eye tracker following training to reflect the mental load accumulated by players during the training sessions. Nine semi-elite soccer players performed two training sessions, based on large-sided games, on an artificial grass field. These two sessions were composed of the same tasks but varying the required time to complete the task goals (Session 1: No time limitations to perform the tasks; Session 2: Limited time to perform the tasks). The participants performed, before (pre-test) and after (post-test) each training session, a prosaccade task in a room near the playing field. Findings revealed a differentiated effect of the available time to complete the training tasks on ocular metrics because significant differences were found in all variables after training (p < .001 for pupil diameter; p < .01 for saccade accuracy and number of saccades; p < .05 for saccade velocity and latency). Ocular metrics could be a promising tool to evaluate mental load following practice because they were sensitive to the time-task constraint, providing researchers a valuable information for a better planning of the mental workload when designed training tasks.

ABSTRACTThe aim of the study was to address the influence of past and current motor experiences as soccer players in a sample of amateur soccer referees when judging ambiguous foul situations occurring in real soccer matches. A case design was used to evaluate the contribution of these motor experiences as soccer playerson the accuracy of referees’ decisions. Specifically, the participants were four referees without motor experiences as soccer players (no ME), four referees with past motor experiences as soccer players (past ME), and four referees with current experiences as soccer players (current ME). The decisions of each referee were assessed during a soccer game, with a total of 80 ambiguous actions. The percentage of correct decisions was 83.8% (current ME), 70% (past ME), and 50.3% (no ME), revealing an impact of motor experiences on decisions of amateur referees. Referees with current motor experiences showed higher sensitivity (d′) making decisions than the other two referee groups. Specific decision biases (c) were also observed. In that, referees without motor experience called fewer fouls for incidents that were categorised as fouls, and referees with the current motor experience called more fouls for incidents that was categorised as no foul. These findings seem to reveal a differential contribution of the motor experiences as soccer players in the decision making of amateur referees judging ambiguous fouls during real soccer matches. The effects seem to depend on whether bodily experiences are present in general and whether they are current or past bodily experiences.

The study examined effects of spatial stimulus–response compatibility on response time and response accuracy in 20 novice combat sport athletes. Two equivalent groups, based on initial reaction time measures, were required to perceive and move quickly and accurately in response to an unspecific visual stimulus presented on a large screen during the two types of perceptual training in eight laboratory sessions. One group reacted by moving the fist toward the stimulus location on the target (direct compatibility condition). Another group was required to move the fist away from target in the opposite direction (indirect compatibility condition). Specifically, the indirect compatibility group achieved faster reaction times than the direct compatibility group during the two posttests containing video-projected attacks of the opponents, and in one of the two posttests containing real opponents’ attacks. Results seem to reveal higher combat performance against real opponents when athletes trained with an indirect stimulus–response compatibility condition.

The aim of the study was to build a low-cost mask-type eye tracker with accuracy and precision levels similar to those reported for commercial eye tracking devices. To this end, head-mounted hardware was designed and developed, while open-source software was modified for digital image capture, manipulation, and fixation analysis. An image recognition application was also included with different lighting scenarios. Moreover, parallax and viewing perspective errors were controlled to ensure the quality of data collection. The device was wireless and lightweight (99 g) to allow for natural movement and avoid participant discomfort. After calibration of a 9-target monocular grid, spatial accuracy and precision of the eye tracker was evaluated by 30 participants, at four different lighting setups, both before and after a climbing task. Validity tests showed high levels of accuracy in all conditions as evidenced by a systematic error for a 13-target grid of <0.5°. The reliability tests also showed consistent measurements with no differences in accuracy recorded between participants, lighting conditions, and visual behaviors for the pre- versus post-climbing task. These results suggest that the present eye tracker reports spatial accuracy similar to other commercial systems with levels of high quality. Altogether, this innovative user interface is suitable for research purposes and/or performance analysis in physical activity and sport-related activities. Also, features of this mask-type eye tracking system make it a suitable perceptual user interface to investigate human–computer interactions in a large number of other research fields including psychology, education, marketing, transportation, and medicine.

El estudio compara el comportamiento visual y motor de 40 tenistas noveles en laboratorio (2D) y en pista de tenis (3D) cuando visualizan una secuencia de passing-shotsejecutada por un oponente experto desde el fondo de la pista. Los tenistas deben responder rápida y precisamente mediante un armado de volea de derecha o de revés según la dirección del golpeo. Para el registro del comportamiento visual, se utiliza el sistema tecnológico ASL SE 5000, mientras que para el comportamiento motor, se adapta un sistema tecnológico para el entrenamiento de las habilidades motoras abiertas. Las variables dependientes son: el tiempo de fijación visual en cada localización corporal o espacial; el tiempo de reacción y de movimiento, tiempo de respuesta (o suma de las dos variables anteriores), y eficacia de la respuesta. Los resultados evidencian que la muestra de tenistas noveles se fija más en la zona central del cuerpo del oponente (tronco, cadera) y son más rápidos en 2D. En cambio, en 3D se fijan más en la zona superior del oponente (cabeza, hombros). Por lo tanto, los tenistas desarrollan un comportamiento visual y motor diferenciado según perciban el movimiento del oponente de forma videoproyectada o en pista de tenis. Se recomienda diseñar tareas representativas en laboratorio que ofrezcan a los deportistas procesos de percepción y de acción similares a situaciones reales de competición.

In this study we assessed the contribution of augmented probabilistic information on the motor behavior of novice defenders during 1 vs. 1basketball play. More specifically, we aimed to investigate the influence of different probabilities of attacks to the basket (Level 1: High-probability of a single attack action; Level 2: Equal probability of two attack actions; Level 3: No-probability of an attack) on defensive reactions and their efficacy. Twenty-six novice participants volunteered and were assigned into three groups, based on their reaction time performance. Each participant performed 10 trials defending against typical basket attacks on a standard basketball court. Three experimental groups were primed regarding the probabilities of two forms of attack, either shooting at the basket or dribbling-past the defender (Group 1: 80% vs 20%; Group 2: 50% vs 50%; Group 3: No-probability of attack). Participants reacted earlier and with greater accuracy in the high-probability condition (80% vs 20%), than in the remaining conditions. We found that, in absence of kinematic information about their opponents, novice basketball players may have relied on the prior information we provided regarding an opponents’ preferred actions during 1 vs. 1basketball play. The provision of probabilistic information could be used as a training strategy to guide the defensive motor behaviors of novice basketball players when facing their counterparts in ball possession by favoring the use of anticipatory information to react earlier and successfully to the opponents’ actions.