Executive functions (EFs) enable flexible thinking, something young children are notoriously bad at. For instance, in the dimensional change card sort (DCCS) task, 3-year-olds can sort cards by one dimension (shape), but continue to sort by this dimension when asked to switch (to color). This study tests a prediction of a Dynamic Neural Field (DNF) model that prior experience with the post-switch dimension can enhance 3-year-old’s performance in the DCCS task. In Experiment 1A, a matching game was used to pre-expose 3-year-olds (n=36) to color. This facilitated switching from sorting by shape to color. In Experiment 1B, 3-year-olds (n=18) were pre-exposed to shape. This did not facilitate switching from sorting by color to shape. The DNF model was used to provide a mechanistic explanation for this asymmetry.