Event-related potentials to intact and disrupted actions in children and adults.

The current research used event-related potentials (ERPs) to investigate neurophysiological responses to intact and disrupted actions embedded within an event in children and adults. Responses were recorded as children (24-month-olds) and adults observed a relatively novel event composed of three actions. In one condition pauses were inserted at intact boundaries (i.e., at the endpoint of each action), whereas in the other condition they were inserted at breakpoints that disrupted the action (i.e., in the middle of each action). Evoked responses revealed differences across conditions in both groups; disrupted actions elicited a prolonged negative slow wave from 100 to 700 ms in children, whereas adults demonstrated two distinct negative peaks between 50-150 and 250-350 ms. These findings contribute the first electrophysiological evidence that children readily detect disruptions to ongoing events by the end of the second year, even with limited exposure to the event itself. Furthermore, they suggest that adults rely on two distinct mechanisms when processing novel events. Results are discussed in relation to the role of perceptual and conceptual levels of analysis in the development of action processing.