Schizophrenia appears quite similar across a range of cultures. However, variability has been noted, and understanding the variant and invariant features of the disorder is necessary for elucidating its biological and environmental basis. Evidence of prominent emotion processing deficits in schizophrenia, including perceptual and experiential aspects, led us to extend the paradigm of standardized measures cross-culturally. We assessed performance of American, German, and Indian patients with schizophrenia and healthy controls on standardized emotion discrimination and experience (mood induction) procedures using happy, sad, and neutral facial expressions of Caucasian actors. Participants were 80 Americans (40 patients; 40 controls), 48 Germans (24 patients; 24 controls), and 58 Indians (29 patients; 29 controls). Face discrimination performance was impaired across patient groups, but was most impaired in those of Indian origin. Lower performance was also found in Indian controls, relative to their American and German counterparts. Mood induction produced weaker effects in all patient groups relative to their respective controls. The results supported the feasibility of cross-cultural comparisons and also emphasized the importance of poser ethnic background for facial affect identification, while poser ethnicity was less consequential for mood induction effects. Emotion processing deficits in schizophrenia may add to the clinical burden, and merit further examination.
While emphasizing the biological substrates of schizophrenia, Kraepelin also pioneered efforts to develop comparative sociocultural psychiatry (reviewed in Jilek, 1995) and encouraged examination of syndrome variability that may be imposed by cultural differences. More recently, emphasis on standardized approaches to diagnosis and assessment, embodied in the DSM and ICD nosologies, has stressed features that are culturally invariant (American Psychiatric Association, 1994). Nonetheless, considerable evidence has accumulated of systematic cross-cultural variability (reviewed in Thakker and Ward, 1998). Although features such as neurocognitive deficits, brain abnormalities, and the effects of some family interaction patterns appear culturally invariant (e.g., Bobes et al., 1996, Chen et al., 1996, Taleb et al., 1996 and Weisman et al., 1998), many features do show substantial variance associated with culture. These include cultural differences in presentation, severity, course, and medication effects (e.g., Bhugra et al., 1996, Collazo et al., 1996, Dassori et al., 1995, Davidson and McGlashan, 1997 and Kent and Wahass, 1996). Moreover, well-established sex differences, such as later age of onset and improved course and outcome (Goldstein and Tsuang, 1990), do not seem to be equally pronounced in all cultures (Jablensky and Cole, 1997).
