Eye movements for performance. Saccades and microsaccades in elite table tennis players

Aim: Investigation of the combined occurrence and characteristics of saccades and microsaccades during free-viewing sport task, with the intention to explore gaze behaviour that would optimize information gathering for action outcome prediction. Methods: Gaze behaviour of expert and novice table tennis players was recorder during a task in which subjects were instructed to predict the ball future direction after the opponent’s throw. Response accuracy, reaction time, fixations, microsaccades and saccades were recorded to estimate the relationship between gazing strategy and success in the task. Analysis of the sequence of saccades/fixations and microsaccade dynamics (during fixations) allowed to study allocation of overt or covert attention in successful predictions. Results: Compared to novices, experts showed more correct responses (70% vs. 64%) with shorter reaction time (411.88±94.62 vs. 468.56±123.22 ms). Experts fixated more times and for longer periods, with more saccades and microsaccades, on hand-racket during forehand and on trunk during backhand drive technique. Furthermore, experts showed a narrower frequency distribution of microsaccade orientations when fixating on hand-racket and trunk areas, meaning that the attention was focused on those small locations. Conclusions: Microsaccades and saccades can be related to the salience of interest areas during performance. Athletes who play ball games are repeatedly exposed to motion stimuli during their training, improving their perception of moving objects. The link between visuomotor performance and covert attention shifts could have a potential impact upon sports, as for example assessments of visual performance that can help to predict people who have elite potential. On these premises, one can suggest that vision training offers a mean to improve performance. References: 1. Piras A, Raffi M, Lanzoni IM, Persiani M, & Squatrito S. (2015) Microsaccades and prediction of a motor act outcome in a dynamic sport situation. Invest Ophthalmol Vis Sci Title, 56(8), 4520–4530. 2. Piras A, Lanzoni IM, Raffi M, Persiani M, & Squatrito S. (2016). The within-task criterion to determine successful and unsuccessful table tennis players. Int J Sports Sci Coach, 11(4).