TEMPORAL AND SPATIAL OCCLUSION OF ADVANCED VISUAL INFORMATION CONSTRAIN EMERGENT COORDINATION OF ONE-HANDED CATCHING BEHAVIOURS

Introduction Dynamic interceptive actions, like catching, are performed under severe spatial and temporal constraints. Here, behavioral processes underpinning one-handed catching was examined using a novel spatial and temporal occlusion design which enabled precise control of pre-release visual information of an actor and a fully coupled action response. Methods An integrated video and ball projection machine was used to create four temporal occlusion and five spatial occlusion conditions of an actor throwing a ball towards participants. Twelve participants’ hand kinematics and gaze behaviors were recorded while attempting to catch a projected ball synchronized with the video footage. Results Temporal occlusion findings revealed that when footage was occluded at earlier time points, catching performance decreased. Movement onset of the catching hand and initiation of visual ball tracking emerged earlier when footage of the thrower was occluded at a later time point in the throwing action. Spatial occlusion did not affect catching success, although movement onset emerged later when increased visual information of the actor was occluded. Later movement onset was countered by greater maximum velocity of the catching hand. The final stages of action (e.g., grasping action of the hand) remained unchanged across both spatial and temporal conditions suggesting the later phases of the action were organised using ball flight information. Discussion Findings revealed how catching behaviors were continuously (re)organized and adapted as information became available in task performance, first by using kinematic information of a thrower's actions, and then by ball flight information. This highlighted the importance of maintaining information-movement coupling during performance of interceptive actions, with these behavioral adaptations having important implications for research that assesses interceptive skills based solely on pre-ball flight information, as in many current video-based simulation paradigms. Contact Joseph.stone@shu.ac.uk