Page 137 - Like me, or else... - Michelle Achterberg

Longitudinal changes of brain and behavior
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negative/neutral feedback, comparable to the behavioral results showing a stronger reduction over time in aggression following positive feedback. Interestingly, AI and DLPFC also showed opposite relations to aggression. Even though both regions increased in activation over time, stronger AI activity was associated with more behavioral aggression and stronger DLFPC activity was associated with less behavioral aggression. The AI results are comparable to a previous finding in adults with low executive control functions, showing that for individuals with low executive control AI activity and aggression were positively correlated (Chester et al., 2014). Even though we did not observe changes in AI activity over time, an interesting direction for future research will be to examine whether this relation is stronger in childhood than adolescence and adulthood, when executive control functions increase.
The positive relation between DLPFC activity and aggression regulation was confirmed in several analyses. First, bilateral DLPFC activity was the only neural predictor in a whole brain regression analysis for aggression control following negative relative to neural feedback. These findings fit well with two decades of research pinpointing the DLPFC as an important regions for cognitive control development (Luna et al., 2004; Luna et al., 2010; Crone and Steinbeis, 2017). The current study extends this finding to the novel domain of social interactions, and demonstrates that the same ‘cold’ regulatory control functions are also important for regulation ‘hot’ emotions in social evaluation contexts (Zelazo and Carlson, 2012; Welsh and Peterson, 2014). Moreover, DLPFC activity also explains individual differences in emotion regulation following rejection. A change-change analysis confirmed that those children who showed the largest increase in DLPFC activity after negative social feedback, also showed the largest reductions in behavioral aggression following negative feedback. This study was performed in a relatively small age range, from 7-9-year old to 9-11-year old, to provide a detailed analysis of changes in childhood. The results provide a window for understanding individual differences in these developmental trajectories, showing that some children develop stronger regulation skills already in childhood. Future research should examine these questions in a longer developmental time window (including more time points) using large samples, which allows disentangling general developmental patterns from individual differences in trajectories.
An intriguing question for future research is whether and how social influences impact individual differences in developmental trajectories. In this study, we addressed this question by examining the effects of a randomized control parenting intervention. Behavioral genetic analyses revealed mostly environmental influences on both behavior and brain (moderate effects of shared environment). Therefore, it was unexpected that we did not find effects of the parental intervention on brain and behavioral outcomes. Although previous studies using VIPP-SD in younger children reported transfer effects (i.e., less externalizing problems in children (Juffer et al., 2017a)) the current study did not
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