ABSTRACT
Abstract From a knowledge-based interaction with the visual environment, the object of this study was to analyse the visual search activity of subjects solving specific tactical problem situations in soccer, and to determine the characteristics of the search patterns. Thirty male subjects participated in the experiment; 15 subjects were seriously involved in soccer and 15 others had little experience in soccer competition. Each subject was presented with 30 simulated offensive situations, presented dynamically by means of 16-mm film display. In response to a signal on the film, the subject had to realize his answer (shoot, dribble, pass to a free partner), as fast and precisely as possible. Eye movements were recorded by an NAC-V-Eye-Movement Recorder. The results showed that expertise results in economy of visual search, the experts having fewer fixations, shorter mean duration fixations leading to shorter response times and a higher response adequacy. In summary, the theoretical assumption can be accepted that experts in a particular discipline differ from non-experts in the amount and type of knowledge they possess and in the way in which they process available information. Further, the results of these sport-specific tasks provide a certain insight into the knowledge structure of players with a different background experience and how they change in function of increasing competence. Both the construction of declarative knowledge and the ability of compiling and 'tuning' are discussed as 'software' attributes.
