Intact spontaneous emotional expressivity to non-facial but not facial stimuli in schizophrenia: An electromyographic study.

Emotional stimuli, such as facial expressions, reliably evoke rapid, spontaneous and covert facial reactions in the perceiver that reflect the affective valence of the observed stimulus. These physiological reactions have been linked to a variety of social cognitive processes known to be disrupted in schizophrenia, such as emotion recognition and affective empathy. Moreover, individuals with schizophrenia exhibit atypical rapid facial reactions when observing emotional expressions. The current study aimed to determine if the disruption in schizophrenia is specific to facial expressions, or instead reflects more generalised emotional or motor impairments in the elicitation of this rapid facial response. Here we quantified activity in the corrugator supercilii and zygomaticus major muscle regions using electromyography while individuals with schizophrenia (n = 24) and controls (n = 21) viewed images of facial and non-facial emotional stimuli. The results indicate that schizophrenia is marked by a disruption in rapid facial responding to facial expressions, but intact responding to non-facial emotional stimuli. This dissociation between the processing of facial and non-facial emotional stimuli points to the need for a greater understanding of the degree to which facial emotion processing impairments contribute to disruptions in mimetic responding in this population.