Although previous ERP studies have demonstrated slowing of visuospatial and motor processes with age, such studies frequently included only young and elderly participants, and lacked information about age-related changes across the adult lifespan. The present research used a Simon task with two irrelevant dimensions (position and direction of an arrow) to study visuospatial (N2 posterior contralateral, N2pc) and motor (response-locked lateralized readiness potential, LRP-r) processes in young, middle-aged, and elderly adults. The reaction time and motor execution stage (LRP-r) increased gradually with age, while visuospatial processes (N2pc latency) were similarly delayed in the older groups. No age-related increase in interference was observed, probably related to a delay in processing the symbolic meaning of the direction in older groups, which was consistent with age-related differences in distributional analyses and N2pc amplitude modulations.
Keywords: Age-related slowing; Event-related potentials (ERPs); Motor processes; Simon task; Visuospatial attention.
Copyright © 2013 Society for Psychophysiological Research.