Brain mechanism of response execution and inhibition: an event-related potential study

High-density event-related potentials were directly recorded to examine the electrophysiologic correlates of response execution (simple response), response inhibition (delaying response), and response imagination (imagining response) after response signals were provided. Results indicate that the simple response elicited a more positive event-related brain potential deflection (P370) than did the baseline task between 250 and 400 ms. Furthermore, two generators localized in the temporal-occipital junction and the anterior cingulate cortex contributed to this effect, which is possibly related to the identification and evaluation of stimulus and response monitoring. The delayed response also elicited a more negative event-related brain potential deflection (N470) than did the baseline task between 400 and 500 ms, and one generator localized in the anterior cingulate cortex, which was possibly related to response inhibition.