Objectives: To explore the interference by facial expressions in schizophrenia (SZ) and bipolar disorder (BD) by manipulating the perceptual load, a determinant for selective attention.
Background and aims: SZ and BD are debilitating neuropsychiatric conditions, often considered as a part of a continuum of psychotic disorders. Attentional deficits have been widely reported in both disorders, particularly in the presence of emotional stimuli such as facial expressions. However, while cognitive deficits are a core feature of SZ, the relationship between SZ and BD is still far from understood. 
Material and methods: 22 SZ patients, 20 BD patients and 22 healthy controls performed a target-letter discrimination task. Participants were asked to discriminate the target-letter among distractor-letters and to ignore a task-irrelevant picture (angry, happy or neutral face). The distractor-letter could be identical (low load; less demanding condition) or different (high load; more demanding condition). Response time and accuracy rate were analysed. 
Results and conclusions: SZ and BD patients showed a significantly higher response time than controls at high load. Concerning accuracy rate, no main group effect was reported. Nevertheless, SZ patients showed a lower accuracy for happy faces, compared to neutral faces, regardless of the load. The results suggest that SZ and BD patients are more prone to distraction by facial expressions, which is in accordance with studies reporting that SZ and BD share similar attentional deficits. In addition, the higher interference of happy suggests the presence of facial emotional perception abnormalities in SZ but not in BD. These findings may provide innovative approaches regarding distraction by emotional stimuli in psychotic disorders.

INTERFERENCE BY FACIAL EXPRESSIONS UNDER PERCEPTUAL LOAD IN SCHIZOPHRENIA AND BIPOLAR DISORDER