Modulatory role of the right ventrolateral prefrontal cortex in crowd emotional perception following social exclusion

The right ventrolateral prefrontal cortex (rVLPFC) is a crucial region involved in modulating social exclusion. Although prior studies have focused primarily on how social exclusion influences the perception of single faces, the effect of social exclusion on the crowd emotional perception and the neural mechanisms remain elusive. The current research examined whether social exclusion causes a biased perception of crowd emotions, and whether this effect would be modulated by transcranial magnetic stimulation (TMS) over the rVLPFC. Participants were either socially included or excluded, while TMS stimulation was applied over the rVLPFC or the vertex. Next, they viewed sets of happy or disgusted faces and assessed the mean emotions of each set. Socially excluded participants overestimated the mean emotions for disgusted crowd faces compared to socially included participants, which was positively correlated with need threat. Compared to the vertex, stimulating the rVLPFC reduced socially excluded participants' biased perception of disgusted crowd faces. Moreover, stimulation of the rVLPFC decreased discrimination performance for crowd faces expressing disgust but increased it for happy crowd faces. The results provide a causal test for the role of rVLPFC in alleviating the biased perception of negative crowd emotions following social exclusion.