Individual differences in planning behavior and working memory: A study of the Tower of London

The relation between individual differences in working memory and performance on the Tower of London (TOL) was investigated under conditions of minimum constraints. On-line planning is likely to occur under such conditions. Measures of verbal and visuo-spatial working memory were administered along with two measures of task-switching executive control. The tasks were individually administered to 51 normal adults. While all participants developed a solution plan for the TOL, variation was observed in the solution time and the number of excess-moves. The number of excess-moves and solution times were unrelated. Both verbal and visuo-spatial working memory were related to the solution time, but not to the number of excess moves. Performance on the task-switching executives was not related to either the TOL or working memory tasks.