Happy facial expression processing with different social interaction cues: an fMRI study of individuals with schizotypal personality traits.

In daily life facial expressions change rapidly and the direction of change provides important clues about social interaction. The aim of conducting this study was to elucidate the dynamic happy facial expression processing with different social interaction cues in individuals with (n=14) and without (n=14) schizotypal personality disorder (SPD) traits. Using functional magnetic resonance imaging (fMRI), dynamic happy facial expression processing was examined by presenting video clips depicting happiness appearing and disappearing under happiness inducing ('praise') or reducing ('blame') interaction cues. The happiness appearing condition consistently elicited more brain activations than the happiness disappearing condition in the posterior cingulate bilaterally in all participants. Further analyses showed that the SPD group was less deactivated than the non-SPD group in the right anterior cingulate cortex in the happiness appearing-disappearing contrast. The SPD group deactivated more than the non-SPD group in the left posterior cingulate and right superior temporal gyrus in the praise-blame contrast. Moreover, the incongruence of cues and facial expression activated the frontal-thalamus-caudate-parietal network, which is involved in emotion recognition and conflict resolution. These results shed light on the neural basis of social interaction deficits in individuals with schizotypal personality traits.