Expertise and age effects on knowledge activation in chess.

Novice, intermediate, and expert chess players of various ages, playing with two chess pieces on a quarter-section of a chessboard, performed a simple task to detect that the king is in check or is threatened with being in check. Age slowed response for both tasks. An interaction of task and skill revealed differences in diminishing response time between check and threat tasks as skill increased; experts were equally fast on both tasks. Measures of speed and working memory were negatively related to age but unrelated to skill. Skill did not mitigate age-related effects on speed of detection. These results suggest that knowledge-activation processes necessary to assess basic chess relationships slow with age, even in experts.