effects of standard and deviant tones on event-related brain potentials and reaction-times to visual stimuli

This research investigated whether choice reaction time (RT) measures and the P300 component of the event-related brain potential (ERP) could be employed to index the attentional resources associated with performing two near-simultaneous tasks. Specifically, this study investigated the effects of auditory tones on the ERPs and RTs associated with a visual stimulus when the stimuli in both modalities were presented in close temporal proximity. The hypothesis that the ERPs and RTs elicited by the deviant visual stimulus would index the processing demands associated with the auditory modality was confirmed. In general, greater P300 amplitude associated with one task indicates diminished P300 and poorer performance on a second task. The results indicate that P300 may be a sensitive indicator of shared processing resources when two tasks are performed near simultaneously.