GAZE DISCRIMINATION IS UNIMPAIRED IN SCHIZOPHRENIA

Interpersonal communication is largely dependent on interpretation of facial expression and emotion. Difficulties in face processing, and mo re specifically in gaze discrimination, have been described in schizop hrenic patients. According to Baron-Cohen (Mindblindness. M.I.T. Press , Cambridge, MA, 1995), gaze discrimination relies on the functioning of a specific cognitive module, the Eye Direction Detector (EDD). It h as been proposed [Rosse et al. (1994) Gaze discrimination in patients with schizophrenia: preliminary report. American Journal of Psychiatry 151, 919-921] that an impairment in gaze discrimination is present in schizophrenia, and plays a fundamental role in inducing the paranoid symptoms reported by many patients. However, in the previous studies, gaze direction detection and interpretation of gaze have never been co mpletely dissociated. The present experiment attempts to test the schi zophrenics' skill in a simple gaze direction detection task. A series of photographic portraits of models looking at different directions ha ve been presented to 22 schizophrenic patients and 36 control subjects . For each portrait subjects were asked to determine whether gaze was directed to the right or to the left by pressing a keyboard key. A for ced choice paradigm was used. No differences were reported between sch izophrenic patients and control subjects. That is, in the present para digm, schizophrenic patients did not show any specific impairment in d etecting the direction of gaze of the portraits. The results are discu ssed according to the notion that a dissociation is present in schizop hrenia between implicit and explicit processes. The present case illus trates how the more automatic elementary functions, such as the detect ion of gaze direction, may be spared in schizophrenic patients, wherea s explicit cognitive functions are likely more affected. (C) 1998 Else vier Science Ireland Ltd. All rights reserved.