Conflict and control: How does the brain regulate cognitive control in the presence of conflict?

摘要

Cognitive control refers to the brain's ability to control attention and other cognitive functions in the service of intention-driven behaviors; moreover, it is an essential aspect in cognition. Cognitive control is commonly evaluated through the so-called conflict adaptation effect, which is revealed through trial-to-trial changes in performance after experiencing cognitive conflict. The conflict monitoring theory is a prominent theory intended to describe conflict adaptation and explain how cognitive control might be engaged in the face of conflict. A passive carryover account, originally aimed at explaining task switching and based on parallel distributed processing models, may represent a superior alternative to the conflict monitoring account. In the carryover account, passive inertia of the cognitive control state explains the trial-to-trial modulation of conflict effects. One problem with conflict adaptation is that the typical paradigms used to create conflict adaptation often include trial-to-trial repetitions that mimic the same performance pattern through priming. Conflict monitoring theory also has difficulty explaining other issues such as whether conflict adaptation is task-specific. A meta-analysis of the so-called conflict adaptation effect suggests trial-to-trial repetitions do not entirely account for conflict adaptation effects, but these effects do appear to be task-specific. The meta-analysis also suggests the withdrawal of control is episodic rather than temporal and conflict adaptation may be sensitive to experimental session length. A novel eye-tracking paradigm addresses the timing of control engagement. The results suggest dynamic regulation of attention coupled with conflict detection. This more tightly coupled detection and regulation process in the context of conflict adaptation is more consistent with a carryover account than what would be expected from the conflict monitoring theory. A subsequent eye-tracking paradigm further supported that trial-to-trial modulations of control are generally more consistent with a carryover account than they are with the conflict monitoring theory. Overall, the empirical evidence points toward a carryover model of cognitive control.