Schizophrenia patients' perceptual biases in response to positively and negatively valenced emotion chimeras

Background. In a prior study, we observed that schizophrenia patients display atypical perceptual biases in response to emotional (happy/neutral) facial chimeras. Methods. The present study was an attempt to replicate and extend those findings, using emotional stimuli with negative affective valence (angry/neutral chimeras) as well as positive valence, and including more than one type of non-affective facial comparison task. We compared schizophrenia patients (N = 37) and controls (N = 48) on free-vision tasks that typically yield left spatial field biases indicative of right hemisphere activation. There were six chimera tasks, including two emotion (happy, angry) chimeras, two non-emotion (gender, age) chimeras and two non-face (dots, gradients) chimeras. Results. We observed a Group x Task interaction, with schizophrenia patients displaying significantly less of the expected left spatial perceptual bias in response to the happy/neutral chimeras and the angry/neutral chimeras relative to the controls. In contrast, the patients and controls did not differ in terms of their response to the Gender, Age, Dots, or Gradients tasks. Conclusions. These findings are consistent with the assertion that, compared with healthy controls individuals with schizophrenia perceive emotion differently.