Preschoolers can form abstract rule representations regardless of cognitive flexibility.

The abstractness of rule representations in the pre-switch phase of the Dimensional Change Card Sorting (DCCS) task was studied by letting 3- and 4-year-old children perform a standard DCCS task and a separate generalization task. In the generalization task, children were asked to generalize their sorting rules to novel stimuli in one of three conditions. In the relevant change condition, values of the relevant dimension changed; in the irrelevant change condition, values of the irrelevant dimension changed; and in the total change condition, values of both dimensions changed. All children showed high performance on the generalization task in the relevant change condition, implying an abstract rule representation at the level of dimensions ("same colors go together"). Performance in the relevant change condition was significantly better (and faster) than performance in the other two conditions. Children with high cognitive flexibility (switchers on the DCCS task) more often switched their attention to the irrelevant dimension in the generalization task only if values of the irrelevant dimension changed. Children with low cognitive flexibility (perseverators) were more often inconsistent in their sorting on the generalization task if values of both dimensions changed. The difference in performance on the DCCS task between switchers and perseverators seems to result from the processes that operate on the learned sorting rules and not from the abstractness of the rule representations children have.