Perception in chess: Evidence from eye movements

We review and report findings from a research program by Reingold, Charness and their colleagues (Charness ef al 2001; Reingold et al. 2001a, 2001b) that employed eye-movement paradigms and provided strong support for the suggestion of de Groot (1946, 1965) and Chase and Simon (1973a, 1973b) that a perceptual advantage is a fundamental component of chess skill. We demonstrated dramatically larger visual spans for experts while processing structured, but not random, chess positions. In addition, consistent with the encoding of chunks rather than individual pieces, experts made fewer fixations, and fixated between related pieces, rather than on pieces. It was also shown that chess piece saliency influenced the selection of experts' saccadic endpoints, and that experts completed the perceptual encoding phase and started the problem-solving phase sooner than intermediates. Finally, we demonstrated that experts, but not less-skilled players, extract chess relations using automatic and parallel procedures.