Page 48 - Like me, or else... - Michelle Achterberg

Chapter 2
negative and positive feedback (Achterberg et al., 2016b). Indeed, an ROI analysis of this mPFC/ACCg region based on the adult study (Achterberg et al., 2016) confirmed elevated activity after rejection in children. A recent review on the ACC and social cognition (Apps et al., 2016) describes an anatomical and function subdivision between the anterior cingulate cortex’ sulcus and gyrus. The region described as the ACC gyrus (ACCg; located adjacent and dorsal to the genu of the corpus callosum in humans) shows overlap with the region that showed increased activation after negative social feedback in children (this study) and for general social evaluation in adults (Achterberg et al., 2016b). The ACCg region has been suggested to be sensitive to factors determining the others’ motivation (see Apps et al. (2016)). Moreover, the meta-analysis showed that the anterior insula was more active after negative compared to neutral feedback, which is in line with the results reported in adults (Achterberg et al., 2016b). The anterior insula has been shown to have strong connections (both structurally as functionally) with this ACCg region (Apps et al., 2016) and several neuroimaging studies have pointed towards the anterior insula and midline areas of the brain as important brain regions responding to social rejection (for meta-analysis see Cacioppo et al. (2013); Rotge et al. (2015)).
In addition, the meta-analysis showed significantly more activation in the amygdala after negative feedback compared to positive feedback. A recent cross- sectional study of 112 participants with ages ranging from 6-23 years showed decreased amygdala reactivity over age, suggesting a shift from bottom-up amygdala based processing to a more top-down processing in adolescence and adulthood (Silvers et al., 2016a). That study focused on the processing of negative and positive scenes and showed strongest reactivity for emotional scenes in general (independent of valence) in younger participants. This may indicate that the amygdala serves as an important region for processing affectively salient stimuli in childhood in particular. An interesting question for future research is to examine how amygdala response to social feedback relates to social behavior in childhood and how it unfolds over time during childhood and adolescence.
Interestingly, in the meta-analyses, we did not find significantly more activation in any of the regions after positive feedback (compared to neutral feedback), which is not in line with previous adult findings (Achterberg et al., 2016b) or with prior studies that focused on adolescents using similar paradigms (Gunther Moor et al., 2010b; Silk et al., 2012). Positivity biases are thought to be larger in childhood than in adolescence or adulthood (Mezulis et al., 2004), possibly indicating that children have a stronger belief that they will be positively evaluated by others. This may result in more salience of neutral or negative feedback relative to positive feedback. Thus, although we found that behaviorally children reacted in a similar way to social evaluation as adults do, the similarities in neural findings between children and adults are more mixed. The neural signature of social rejection in terms of anterior insula and mPFC/ACCg activation was found to be present in middle childhood, but it was less pronounced than in
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