Currently much developmental neuroimaging work on cognitive

Currently, much developmental neuroimaging work on cognitive control has been done using working memory tasks. A recent met-analysis of this literature documented bilateral dlPFC (BA6) activity to significantly increase with age during working memory (Andre et al., 2016). Moreover, from a theoretical, empirical, and anatomical angle, the precise role of the dlPFC in affective contexts remains to be determined because it has few (if any) direct anatomical connections with affective circuitry but is nonetheless involved in top-down regulation of affective neurocircuitry such as the amygdala (Banks et al., 2007) possibly through indirect connections (Ray and Zald, 2012). Indeed, other authors recommend working memory as a valuable task domain for future investigation in emotion cognition integration and to assess the role of the dlPFC in such contexts (Ray and Zald, 2012). Thus, because the anatomical regions, age-related effects, and the role of working memory in top-down control are well-defined (D’Esposito and Postle, 2015), it would appear that this critical cognitive skill is an ideal candidate to test the theory of developmental effects of emotion on cognitive control. Moreover, because the emotional n-back task also includes negative and positive stimuli, it may be suitable to probe all three neuroanatomical regions postulated by the triadic model. The present study investigated the neural correlates of relevant and irrelevant affective stimuli on working memory performance in adolescents and adults. Specifically, it aimed to test the hypothesis that emotional material differentially modulates neural activity in ciprofloxacin areas supporting cognitive control and emotion in adolescents and adults. We had three main predictions. First, we anticipated replicating the previous behavioral finding of speeded responses to happy faces in adolescents relative to adults when emotion was task-relevant. Second, based on a hypothesized imbalance between early limbic system development and delayed prefrontal cortical development by the triadic model (Ernst et al., 2006), we anticipated that adults would show a modulation of emotion with cognitive control in the PFC, whereas such a modulation in adolescents would be apparent in the ventral striatum and the amygdala. Finally, because of heightened sensitivity of the ventral striatum in adolescents to positive information (Ernst, 2014; Ernst et al., 2006; Silverman et al., 2015) and developmental differences in working memory during positive valence (Cromheeke and Mueller, 2016), we predicted improved performance during happy faces relative to other emotional valence in the nucleus accumbens for this group and relative to adults.
Method
Results
Discussion This study tested the hypothesis of differential processing of relevant and irrelevant emotional information in healthy adolescents and adults. Specifically, based on prior work suggesting an imbalance between approach and avoidance related behavior on the one hand and top-down regulation on the other hand (Ernst, 2014), it was hypothesized that adults would show a modulation of emotion with cognitive control in prefrontal cortex, while adolescents would show such modulations in the amygdala and ventral striatum. Several main findings emerged. First, behaviorally and across both age groups, happy faces speeded up response time relative to angry and neutral faces while angry faces reduced accuracy relative to happy and neutral faces. Second, consistent with our predictions, cognitive load modulated responsivity to angry faces in adults but not in adolescents in dlPFC although this was irrespective of task relevance. Third, ventral striatal activity to happy faces was more pronounced in adolescents relative to adults but was also not modified by attention condition (or cognitive load). Fourth, and somewhat unexpected, amygdala activation to happy faces was increased during task-relevant trials in adolescents relative to task-irrelevant trials with no such differences in adults.