Page 135 - Like me, or else... - Michelle Achterberg

Longitudinal changes of brain and behavior
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Figure 4. Whole brain-behavior analyses with all available MRI data at wave 2 (N=360). a) Significant cluster of activation in bilateral DLPFC for negative> neutral social feedback with noise blast (Δ negative-neutral) as regressor. b) Visualization of brain- behavior association at wave 2: increased DLPFC activity after negative feedback is related to decreased aggression. c) Brain-behavior association over time: the change in DLPFC activation is negatively correlated to the change in aggression, with larger increases in DLPFC activity over time being related to larger decreases in aggression.
Genetic and environmental influences
Given that our sample consists of both mono- and dizygotic twins, we were able to test for effects of genetics, shared environment and unique environments. As can been seen in Table 3, behavioral aggression was driven by a combination of genetic, shared and unique environmental factors. Variation in neural activity in the salience ROIs (AI, IFG, MPFC) showed little to no genetic influence, but did show moderate effects of shared environmental effects. Most variation was explained by the unique, non-shared environment (including measurement error). For DLPFC activation, results were inconclusive. There were some indications of heritability (i.e., on individual differences in positive-neutral), whereas individual differences were partly explained by shared environment (negative-neutral). Again, most individual differences were explained by unique non-shared environment (including measurement error).
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