On the use of event-related potentials to auditory stimuli in the Go/NoGo task.

The N2 and P3 components of the event-related potential (ERP) are putative markers of inhibition in the Go/NoGo task. If this is the case, they should be unaffected by stimulus presentation modality. Theoretical researchers have suggested that the effect is smaller or absent with auditory stimuli, while others have shown that the effect depends on the perceptual similarity of the stimuli. Meanwhile, clinical researchers appear to be unaware of the debate. This study examined the N2 and P3 NoGo effects elicited by five sets of auditory stimuli varying in perceptual similarity. The N2 NoGo effect was significant for similar and different letters, and for similar tones, but not for different tones or novel sounds. As expected by the perceptual overlap hypothesis, the largest N2 NoGo effect was observed with the similar letters. In contrast, the P3 NoGo effect was significant and of a similar magnitude for all stimulus sets. The differential effect of the stimulus sets suggests separable underlying processes reflected in N2 and P3. Guidelines are provided for clinical researchers wishing to use auditory stimuli in the Go/NoGo task.