Learning and decision-making are modulated by socio-emotional processing and such modulation is implicated in clinically relevant
personality traits of social anxiety. The present study elucidates the computational and neural mechanisms by which emotionally
aversive cues disrupt learning in socially anxious human individuals. Healthy volunteers with low or high trait social anxiety performed
a reversal learning task requiring learning actions in response to angry or happy face cues. Choice data were best captured by a computational
model in which learning rate was adjusted according to the history of surprises. High trait socially anxious individuals used a
less-dynamic strategy for adjusting their learning rate in trials started with angry face cues and unlike the low social anxiety group, their
dorsal anterior cingulate cortex (dACC) activity did not covary with the learning rate. Our results demonstrate that trait social anxiety is
accompanied by disruption of optimal learning and dACC activity in threatening situations.