Page 71 - Like me, or else... - Michelle Achterberg

The neural basis of aggression regulation
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of activation. The contrast Positive > Neutral feedback also revealed widespread activation in the bilateral insula and mPFC. In addition, the contrast resulted in increased activity in the ventral striatum, the subgenual ACC, as well as regions such as the occipital lobe, as shown in Figure 2c (Table S2). The reversed contrast (Neutral > Positive feedback) resulted in activity in the right insula and right postcentral gyrus (Table S2).
Social evaluation conjunction
The analyses above suggested partially overlapping activation patterns for positive and negative social feedback, relative to a neutral baseline. To formally investigate the regions that were activated both after negative social feedback and after positive social feedback, we conducted a conjunction analyses to explore a main effect of social evaluation. Common activation across both positive and negative social feedback were observed in the insula and the mPFC, as well as the bilateral occipital lobes, including left Fusiform Face Area (FFA), see Figure 2d (Table S3).
Brain-Behavior associations
Noise blast duration
To test the association between brain activity and behavior in response to negative social feedback, we conducted a whole brain regression analysis at the moment of receiving negative social feedback (relative to neutral feedback; Negative > Neutral), with the difference in noise blast duration after negative and neutral feedback as a regressor. This way, we tested how initial neural responses to feedback were related to subsequent aggression. The analyses revealed that increased activation in the right dorsal lateral PFC (dlPFC) was associated with smaller increases in noise blast duration after negative social feedback compared to neutral feedback, see Figure 3. A similar relation was observed for the left amygdala, left hippocampus, and bilateral superior parietal cortex (Table S4). The reversed contrast (positive relation between Negative> Neutral feedback and noise blast length difference) did not result in any significant activation.
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