Multiple cognitive control effects of error likelihood and conflict.

Recent work on cognitive control has suggested a variety of performance monitoring functions of the anterior cingulate cortex such as errors, conflict, error likelihood, and others. Given the variety of monitoring effects, a corresponding variety of control effects on behavior might be expected. This paper explores whether conflict and error likelihood produce distinct cognitive control effects on behavior, as measured by response time. A Change signal task (Brown & Braver, Science 307:1118-1121, 2005) was modified to include conditions of likely errors due to tardy as well as premature responses in conditions with and without conflict. The results discriminate between competing hypotheses of independent versus interacting conflict and error likelihood control effects. Specifically, the results suggest that the likelihood of premature versus tardy response errors can lead to multiple distinct control effects, which are independent of cognitive control effects driven by response conflict. As a whole, the results point to the existence of multiple distinct cognitive control mechanisms and challenge existing models of cognitive control that incorporate only a single control signal.