The influence of aging on cognitive control: The discrepancy between conflict and conflict adaptation effects

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 RTs 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 ACC. 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 RTs were positively related. Together, these findings point to a dynamic cognitive control system that, as a function of previous trial type, up- and down-regulates attention and preparatory motor activities in anticipation of the next trial.

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Exploring the Generality of Transient Cognitive Control: Conflict Adaptation Effects Across Task-Switching and Non-Task-Switching Trial Sequences

PsycEXTRA Dataset ◽

10.1037/e520602012-836 ◽

2011 ◽

Author(s):

Mark E. Faust ◽

Kristi S. Multhaup ◽

Sasha Levons ◽

Kareem Abdelnabi ◽

Anam Barakzai ◽

...

Keyword(s):

Cognitive Control ◽

Task Switching ◽

Conflict Adaptation ◽

Adaptation Effects

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Right Ventrolateral Prefrontal Cortex Mediates Individual Differences in Conflict-driven Cognitive Control

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00064 ◽

2011 ◽

Vol 23 (12) ◽

pp. 3903-3913 ◽

Cited By ~ 45

Author(s):

Tobias Egner

Keyword(s):

Conflict Resolution ◽

Individual Differences ◽

Cognitive Control ◽

Inferior Frontal Gyrus ◽

Group Analysis ◽

Individual Variability ◽

Primary Role ◽

Conflict Adaptation ◽

Traditional Group ◽

Behavioral Expression

Conflict adaptation—a conflict-triggered improvement in the resolution of conflicting stimulus or response representations—has become a widely used probe of cognitive control processes in both healthy and clinical populations. Previous fMRI studies have localized activation foci associated with conflict resolution to dorsolateral PFC (dlPFC). The traditional group analysis approach employed in these studies highlights regions that are, on average, activated during conflict resolution, but does not necessarily reveal areas mediating individual differences in conflict resolution, because between-subject variance is treated as noise. Here, we employed a complementary approach to elucidate the neural bases of variability in the proficiency of conflict-driven cognitive control. We analyzed two independent fMRI data sets of face–word Stroop tasks by using individual variability in the behavioral expression of conflict adaptation as the metric against which brain activation was regressed while controlling for individual differences in mean RT and Stroop interference. Across the two experiments, a replicable neural substrate of individual variation in conflict adaptation was found in ventrolateral PFC (vlPFC), specifically, in the right inferior frontal gyrus, pars orbitalis (BA 47). Unbiased regression estimates showed that variability in activity in this region accounted for ∼40% of the variance in behavioral expression of conflict adaptation across subjects, thus documenting a heretofore unsuspected key role for vlPFC in mediating conflict-driven adjustments in cognitive control. We speculate that vlPFC plays a primary role in conflict control that is supplemented by dlPFC recruitment under conditions of suboptimal performance.

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