The selection and suppression of action: ERP correlates of executive control in humans

A key aspect of higher cortical function is the ability to selectively with hold or suppress action where appropriate. To examine the time course of ex ecutive control we used dense-sensor EEG recording techniques to study even t-related electrical potentials (ERPs during a visual 'go/no-go' task. We s how that during both go and no-go trials there is a positive deflection in the ERP, which develops over posterior parietal sensors similar to 350 ms ( P300) after the onset of a conditional visual stimulus, but. is selectively suppressed during no-go trials. We also show that this modulation of the p arietal P300 is preceded by a negative deflection in the ERP recorded over frontal cortex (N2), which is apparent only for no-go trials. We suggest th at this signal provides an electrophysiological marker in man for the decis ion to withhold the execution of a motor response. NeuroReport 10:861-865 ( C) 1999 Lippincott Williams & Wilkins.