The role of stimulus novelty on children's inflexible dimensional switching

Children's ability to flexibly shift attention between different representational schemes was investigated using the dimensional change card sorting task. Across three experiments (N = 56 three-year-olds and N = 40 four-year-olds in ; N = 14 three-year-olds in ; and N = 14 three-year-olds in ) the role of perceptual information on children's cognitive flexibility was investigated by manipulating different aspects of the task materials between pre- and postswitch phases. Better performance was observed when either task-relevant (the color or shape of the images on the cards) or task-irrelevant information (the background color or shape of the actual cards) was changed, with this improvement occurring when the changes were salient enough to induce a stimulus novelty effect.

The role of perceptual similarity of the task environments in children's perseverative responding

Perseverative responding is often seen in children's performance in a variety of contexts. One such context is symbolic comprehension in which 2- and 2½-year-olds demonstrate difficulty in appreciating the association of symbols (pictures and scale models) and their referents and show a high proportion of perseverative responding. Representational-level explanations of perseveration were explored in the current studies via examination of the impact of perceptual similarity of visual environments across trials. Across two experiments, children saw either a picture (Experiment 1) or a scale model (Experiment 2) of a hiding location of a room and were then encouraged to recover the toy from an identical room. Manipulating the perceptual similarity of the environments across successive trials affected performance and perseverative responding. These results highlight the critical role played by perceptual information not only in symbolic tasks but also in many other tasks and have important implications for theories of perseveration.