The facilitative effect of positive stimuli on 3-year-olds' flexible rule use

This study examined the effect of emotional stimuli on 3- to 4-year old children's flexible rule use, as measured by the Dimensional Change Card Sort (DCCS). In Experiment 1, children in two countries (Canada and China) were given 2 versions of the DCCS. The Standard version required children to sort red and blue boats and rabbits first by shape and then by color (or vice versa); the Emotional Faces version required children to sort happy and sad male and female faces first by emotion and then by gender (or vice versa). Children performed significantly better on the Emotional Faces version, and performance on the 2 versions was related. Order in which dimensions were presented had no effect. Experiment 2 examined which aspects of the emotional faces were responsible for the facilitation of children's performance. Performance on the Standard version was compared to performance on three contextual faces versions, in which children were shown happy, sad, or neutral faces and required to sort them by age (child versus adult) and then by gender (or vice versa). Facilitation was only seen in the context of happy faces. Results are consistent with the suggestion that positive stimuli promote cognitive flexibility, perhaps by increasing dopamine levels in prefrontal cortex.