Functional Activation During a Cognitive Control Task in Healthy Youth Specific to Externalizing or Internalizing Behaviors

Background: Externalizing behaviors are negative behaviors expressed outwardly, including rule breaking, aggression, and risk taking; internalizing behaviors are expressed inwardly, including depression, withdrawal, and anxiety. Such behavior can cause problems in early life and predict difficulties across the lifespan. There is evidence for a relationship between executive function and both externalizing and internalizing. However, although these behaviors occur along a spectrum, there is little neuroimaging research on this relationship in typically developing youth. Methods: We assessed 41 youth (10–19 years of age) using the Multi-Source Interference Task during functional magnetic resonance imaging and related the findings to self-reported externalizing and internalizing scores as measured by the Youth Self-Report. We performed a general linear model using FSL software; externalizing, internalizing, age, and sex were included in the model. Results: Compared to the control condition, the more difficult Multi-Source Interference Task interference condition was associated with greater engagement of the frontoparietal cognitive control system and decreased engagement of regions in the default mode network, based on a cluster threshold of Z > 3.1 (p =.01). When we examined regions uniquely associated with either internalizing or externalizing, we found that within the same group of subjects, higher externalizing behavior was associated with hyperactivity in the parietal lobe; in contrast, higher internalizing behavior was associated with increased activation in the medial prefrontal cortex. Conclusions: These findings suggest that externalizing and internalizing may be associated with altered, but different, patterns of activation during cognitive control. This has implications for our understanding of the relationship between cognitive control and behavioral problems in youth.