Original Research ARTICLE
Information accrual from the period preceding racket-ball contact for tennis ground strokes: Inferences from stochastic masking
- 1Department of Psychology, City University of London, United Kingdom
- 2Department of Psychology, University of Kaiserslautern, Germany
- 3School of Health Sport & Bioscience, University of East London, United Kingdom
- 4Centre for Applied Vision Science, City University of London, United Kingdom
Previous research suggests the existence of an expert anticipatory advantage, whereby skilled sportspeople are able to predict an upcoming action by utilising cues contained in their opponent’s body kinematics. This ability is often inferred from “occlusion” experiments: Information is systematically removed from first-person videos of an opponent, for example by stopping a tennis video at the point of racket-ball contact, yet performance, such as discrimination of shot direction, remains above chance. Here, we assessed the expert anticipatory advantage for tennis ground strokes via a modified approach, known as “bubbles”, in which information is randomly removed from videos at in each trial. The bubbles profile is then weighted by trial outcome (i.e. a correct vs. incorrect discrimination) and combined across trials into a classification array, revealing the potential cues informing the decision. In two experiments (both with N = 34 skilled tennis players) we utilised either temporal or spatial bubbles, applying them to videos running from 0.8 s to 0 s before the point of racket-ball contact (cf. Jalali et al., 2018). Results from the spatial experiment were equivocal, but somewhat suggestive of accrual from the torso region of the body. Results from the temporal experiment, on the other hand, were clear: information was accrued mainly during the period immediately prior to racket-ball contact. This result is broadly consistent with prior work using non-stochastic approaches to video manipulation, and cannot be an artifact of temporal smear from information accrued after racket-ball contact, because no such information was present.
Keywords: Sports, Tennis, occlusion, reverse correlation, Anticipatory ability
Received: 02 Jul 2019;
Accepted: 12 Aug 2019.
Copyright: © 2019 Jalali, Martin, Ghose, Buscombe, Solomon and Yarrow. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Kielan Yarrow, City University of London, Department of Psychology, London, EC1V 0HB, United Kingdom, firstname.lastname@example.org