Sex Differences in Affective Expression Among Individuals with Psychometrically Defined Schizotypy: Diagnostic Implications

The present investigation uses facial electromyography (fEMG) to measure patterns of affective expression in individuals with psychometrically defined schizotypy during presentation of neutral and negative visual images. Twenty-eight individuals with elevated schizotypal features and 20 healthy controls observed a series of images from the International Affective Picture System (IAPS) and provided self-report ratings of affective valence and arousal while their physiological responses were recorded. The groups were evenly divided by sex. A three-way interaction in fEMG measurement revealed that while males with psychometrically defined schizotypy demonstrated the expected pattern of blunted/constricted facial affective expression relative to male controls in the context of negative images, females displayed the opposite pattern. That is, females with psychometrically defined schizotypy demonstrated significant elevations in negative facial affective expression relative to female controls while viewing negative images. We argue that these findings corroborate previously reported impressions of sex differences in affective expression in schizotypy. We discuss implications for assessment and diagnostic procedures among individuals with disorders along the schizophrenia spectrum.