WORKING-MEMORY IN CHESS

Three experiments investigated the role of working memory in various a spects of thinking in chess. Experiment 1 examined the immediate memor y for briefly presented chess positions from master games in players f rom a wide range of abilities, following the imposition of various sec ondary tasks designed to block separate components of working memory. Suppression of the articulatory loop (by preventing subvocal rehearsal ) had no effect on measures of recall, whereas blocking the visuospati al sketchpad (by manipulation of a keypad) and blocking the central ex ecutive (by random letter generation) had equivalent disruptive effect s, in comparison with a control condition. Experiment 2 investigated t he effects of similar secondary tasks on the solution (i.e., move sele ction) of tactical chess positions, and a similar pattern was found, e xcept that blocking the central executive was much more disruptive tha n in Experiment 1. Experiment 3 compared performance on two types of p rimary task, one concerned with solving chess positions as in Experime nt 2, and the other a sentence-rearrangement task. The secondary tasks in each case were both designed to block the central executive, but o ne was verbal (vocal generation of random numbers), while the other wa s spatial in nature (random generation of keypresses). Performance of the spatial secondary task was affected to a greater extent by the che ss primary task than by the verbal primary task, whereas there were no differential effects on these secondary tasks by the verbal primary t ask. In none of the three experiments were there any differential effe cts between weak and strong players. These results are interpreted in the context of the working-memory model and previous theories of the n ature of cognition in chess.