Comparison of Event-Related Potentials of Young Children and Adults in a Visual Recognition and Word Reading Task

An experiment is described in which event-related potentials (ERPs) of a group of young children were compared with ERPs of a group of young adults. Both groups were required to perform a simple word-reading task and a picture-recognition task. Principal components analyses (PCAs) were performed on the averaged ERPs in two different ways: a) separately for each of four combinations of tasks and age groups, and b) separately for each age group (pooled across tasks). The results demonstrated that ERP components of children and adults differed both qualitatively and quantitatively. First, children's ERPs were characterized by a long-latency negative component (N500) and a slow positive wave (SW) component, and adults’ ERPs were characterized by two late positive components (P340 and SW respectively). Second, both children and adults showed an earlier positive component that varied in peak latency between 280 ms for children and 240 ms for adults. In addition, adults showed a marked increase in SW positivity in the word-reading task as compared with the picture-recognition task, while task effects were less manifest in the components of children. These results support the notion that children and adults differed both in speed as well as in their mode of processing under the different task requirements.