Comparison of P300 from passive and active tasks for auditory and visual stimuli.

The P300 event-related brain potential (ERP) was elicited with a stimulus-sequence paradigm for auditory and visual stimuli in separate active and passive task response conditions. Auditory stimuli in the passive task yielded P300 waveforms similar to those obtained from the active task condition. Visual stimuli in the passive task yielded much smaller P300 waveforms that were not morphologically consistent with those from the active task. The results suggest that auditory stimuli produce more robust P300 components than visual stimuli in passive task situations.