Age Three: Milestone in the Development of Cognitive Flexibility

Abstract

Although the cognitive flexibility (CF) of preschool children has been extensively studied, the development of CF in children around three years old is unclear. This study aimed to investigate the CF of three-year-olds in a stepwise rule-induction task (sRIT) comprising nine steps in which children are encouraged to switch attention to a new rule and then implicitly inhibit the old one. A pair of boxes was displayed at each step, and children aged 2.5 to 3.5 years were asked to select the target. When children learned a rule (e.g., the shape rule), they were encouraged to switch rules through negative feedback. The results showed that most children (81.10%) passed at least one of the two sets of the sRIT, and children over the age of three years performed better than those under three years. Additionally, a positive correlation existed between rule switching and rule generalization, whereby the old rule was implicitly inhibited. These findings indicate that age three might be a milestone in the development of CF, and inhibitory control might play a vital role in rule switching.

Keywords: cognitive flexibility; generalization; inhibition; rule induction; switch.

Figure 1

The sample stimuli used in the sRIT.

Figure 2

Sampled stimuli and the test procedure in a set of the sRIT. In the first phase, a child may select the cylindrical boxes and form the rule “the cylindrical boxes contain candy.” In Step 4, the most probable choice is identical to that selected in the preceding two steps. However, the experimenter provides negative feedback and indicates “the candy now is in another box.” In Steps 5 and 6, participants are expected to switch their attention to the new rule (i.e., the boxes with a brick pattern contain a candy). From Steps 7 to 9, children are expected to apply the new rule to boxes with different shapes. Checkmark “√” indicates positive feedback, while “×” indicates negative feedback.

Figure 3

Flowchart of an example in the sRIT. Every step is represented by a pair of rectangular boxes containing exact attributes in the dimensions of pattern and shape. The color yellow indicates the correct choice. Y indicates that the child has made a correct choice, while N indicates that the child has made an incorrect choice. The arrow points to the next step.

Figure 4

Percentage of children who passed the sRIT. * p < 0.05.