Guest Editorial: Visual Function and Sports Performance.

Abstract

Remarkable athletic feats often invoke questions from observers about how these achievements are possible. In baseball, softball, and cricket, how does a batter achieve the remarkable temporal and spatial accuracy in their swing necessary to successfully bat the ball, all while under severe timing constraints? How does a soccer player moving at full speed “thread the needle”with a perfectly placed pass between defenders? Sports are necessarily designed to test the limits of human abilities, and given the vital role of vision in sport, it is important to consider how visual abilities enable or constrain sports performance. The overarching topic in this feature issue is the role of vision in sports performance. This area is clearly of growing interest, with 73% (1985/2713) of the citations returned in PubMed for the search terms “sports” and “vision” occurring since 2010 (on May 1, 2021). As further evidence of the interest and enthusiasm for sports vision, the International Sports Vision Association was formed to advance the field of vision assessment and training for athletes, and the Journal of Sports and Performance Vision began publishing research articles on these topics in 2019. Because sports vision encompasses a wide array of subject matters, the sports vision literature is understandably disseminated throughout many diverse journals thatmay ormaynot bedevoted solely to vision. These journals are centered around topics including vision science, cognition, kinesiology and biomechanics, sports science, neuroscience, learning, and both ocular and systemic clinical issues. The goal of this feature issue is to bring together studies that cover a variety of topical areas in sports vision. There are articles on vision assessments, vision correction and eye protection, cognitive-perceptual issues, vision training, concussion, and retinal physiology. Key questions for sports vision practitioners that are addressed in this feature issue include the following: what visual or vision-related attributes may underpin success in a particular sport, what cues are used by athletes to compete successfully in their sport, what visual assessments are best to measure an athlete s current level of development and to estimate his/her future potential, and which training methods and training environments (e.g., virtual or on-field) result in optimal transfer to athletic competitions. In keeping with the global reach of sports, the articles in this feature issue were contributed by authors from Australia, Belgium, Canada, Germany, Hong Kong, Iran, Japan, the Netherlands, Portugal, Spain, Switzerland, Turkey, the United Kingdom, and the United States. In this feature issue, Erickson s review of visual skills and assessment devices describes the difficult challenge facing practitioners who must determine which of the myriad of visual skills are most important for a particular sport and which assessments are most appropriate to evaluate these skills. The review by Hodges and colleagues in this issue provides a conceptual framework for perceptual-cognitive skills that may aid the sports vision practitioner in determining those abilities to test and train in a particular sport. Hodges and colleagues divide these skills into fundamental skills (static visual acuity, dynamic visual acuity, peripheral vision), low-level visual skills (color perception, contrast sensitivity, stereoacuity and depth perception, motion perception), high-level and attentional skills (visual attention and eye movements), and cognitive skills (memory, situational knowledge, anticipation, decision making, multitasking, inhibition and interference control, cognitive flexibility). Psychophysical studies of perceptual thresholds, studies of the functional limitations of eye movements, and studies of attentional thresholds in the general population and in athletes in particular serve as a basis for hypotheses regarding when and how visual skills could apply to specific sports. Another area of emphasis addressed in this feature issue is the comparison of visual skills between athletes (and referees) across different levels of expertise and across different ages. This includes several original investigations comparing differing levels of expertise, as well as a review by Dalton that addresses the quiet eye phenomena. This influential concept refers to “the final fixation or tracking gaze prior to the onset of a critical motor action,” which has been shown to correlate with performance and overall expertise in athletes. A key thesis underlying these studies of vision in athletic experts is that at least some of the differences found between higherand lower-achieving individuals may form the basis of training approaches that can promote athletic (or officiating) performance. There are some major questions in ball-striking sports such as baseball and cricket that are addressed in this feature issue. These questions include what information is used by athletes in determining when and where an approaching object will arrive to produce an appropriate visuomotor response, and how these cues are combined when generating motor responses. Gray s review in this issue discusses model-based control (primarily predictive and based on internal models of trajectory) versus online control (based on unfolding visual information) models. Much like the information gained in comparing expert and less expert or novice athletes, an understanding of how action is controlledmay help to guide the development of sports vision training techniques. Another question that has generatedmuch interest in the sports vision literature is that of coupled versus uncoupled responses. In an uncoupled response, the observer s response is not the same as that required in a game. For example, in cricket, a coupled response would involve a batter attempting to strike approaching balls, whereas an uncoupled response might require the batter to verbally assess when or where the pitched ball will arrive. There is a growing literature suggesting that performance as assessed with coupled responses does not necessarily match performance when measured with uncoupled responses. As described byMann and colleagues in this issue, it has been suggested that differences in coupled and uncoupled responses could be explained by the twovisual-systems hypothesis, wherein uncoupled responses require an overreliance on the ventral system, whereas the dorsal system is primarily used in coupled responses. This discussion of coupled EDITORIAL