Improving postswitch performance in the dimensional change card-sorting task: the importance of the switch and of pretraining by redescribing the test cards.

The dimensional change card-sorting task (DCCS) is used to assess the executive abilities of young children. Typically, 3-year-olds have difficulty in performing this task. However, the exact nature of this difficulty is still being debated. In the standard DCCS, children need to sort, for example, test cards with a blue flower or a red car into two boxes marked with the target cards. The 3-year-olds commonly have pronounced difficulty in switching from one sorting criterion (e.g., color) to another (e.g., shape). Here two experiments with 3-year-olds showed that making the transition between the sorting criteria more distinct improved performance significantly. This was achieved by taking away the target cards for a brief time period, asking a question irrelevant to the task, and pretraining the children by redescribing the test cards.