Dynamic adjustments of cognitive control: Oscillatory correlates of the conflict-adaptation effect

It is a prominent idea that cognitive control mediates conflict adaptation, in that response conflict in a previous trial triggers control adjustments that reduce conflict in a current trial. In the present EEG study, we investigated the dynamics of cognitive control in a response-priming task by examining the effects of previous-trial conflict on intertrial and current-trial oscillatory brain activities, both on the electrode and the source level. Behavioral results showed conflict-adaptation effects for response times and response accuracy. Physiological results showed sustained intertrial effects in left-parietal theta power, originating in the left inferior parietal cortex, and midcentral beta power, originating in the left and right (pre)motor cortex. Moreover, physiological analysis revealed a current-trial conflict-adaptation effect in midfrontal theta power, originating in the anterior cingulate cortex. Correlational analyses showed that intertrial effects predicted conflict-induced midfrontal theta power in currently incongruent trials. In addition, conflict-adaptation effects in midfrontal theta power and reaction times were positively related. Together, these findings point to a dynamic cognitive-control system that, as a function of previous-trial type, up- and downregulates attention and preparatory motor activities in anticipation of the next trial