Virtual goal- keeping: Understanding how perception influences decisions about action

Abstract

According to humans and animals perceive and interact with surfaces (e.g. grass), places (e.g. pitch), objects (e.g. ball) and events (e.g. a set-play) (Gibson, 1966). All these so called properties of the surrounding environment provide opportunities for action. This relationship between the environment and player and the ensuing action possibilities are known as affordances. Affordances are essentially the starting point for psychologists trying to understand how humans perceive, learn, and decide to act upon events they perceive to be taking place in their surrounding environment (Turvey, 1992). This area of psychology assumes a player-environment to perceive and perceive to move processes and action capabilities are therefore intricately linked and play a crucial role in the decision making process.Virtual reality provides the perfect adjunct to study perception/action in sport. It is in essence a sophisticated interactive and immersive humancomputer interface where a sensory environment (visual, haptic and/or acoustic) is simulated by a computer and is controlled by the interactive behaviour of the user. It is a versatile methodological tool that gives the experimenter complete control over complex environmental conditions and allows for an inpsychology this technology is starting to be exploited as a means of treating phobias (VRET), monitoring behaviour of autistic children in virtual classrooms, rehabilitating stroke patients and most recently in testing perception/action capabilities in elite sports players (Bideau et al, 2006;Craig et al, 2006). The versatility of the VR platform means the technology can be easily applied to a multitude of sports.For instance, the systematic variation of the visual information available to the players (e.g. the ball trajectory and/or the run-up of the attacking/defending player) will influence the way actions are guided. The objective of the research presented here is to determine how visual information picked up from the visual environment influences the actions and decisions being made by the players in the game of soccer. For instance, deciding when and how to move is very important when keeping goal in soccer. Goal-keepers must attend to pertinent visual information (player and ball) that will allow them to judge where the ball is going, to get their body in the right place at the right time. However, more and more teams are exploiting the free-kick scenario as an opportunity for scoring goals (Grant et al, 1999). This appears to be related to the freedefensive wall. Why do players try to put spin on the trajectory make it more difficult for the goal-keeper to anticipate where the ball is going and subsequently control their actions to actually get there? In other words does spin give the attacker a competitive advantage?This talk will present experimental work that significantly how to act (Craig et al, 2006). By immersing players in a virtual soccer stadium and allowing them to interact with realistic curved free kicks we show to what extent the impact up...