Brain activation during eye gaze discrimination in stable schizophrenia
Christian G Kohler1, James Loughead, Kosha Ruparel
1Neuropsychiatry Division, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, United States. kohler@upenn.edu
Objective:
Earlier studies described gaze discrimination impairment in schizophrenia. The purpose of this study was to compare gaze discrimination abilities and associated brain activation in persons with stable schizophrenia and matched controls.
Methods:
13 schizophrenia and 12 healthy participants underwent a gaze discrimination task with face stimuli rotated at 0, 4 and 8 degrees deviation. During fMRI with BOLD imaging, subjects were asked to identify whether a face was making eye contact. Subject-level parameter estimates for BOLD signal change were entered into an orientation by group mixed effect repeated measures ANOVA.
Results:
Gaze discrimination performance did not differ between groups. Patients showed decreased activation in areas of bilateral inferior frontal and occipital areas, and select temporo-limbic regions, including amygdala. Groups differed by activation patterns according to gaze deviation. In controls, faces with 4 degrees deviation produced higher activation in frontal and temporal regions. In patients, 0 degrees deviation produced increased activation in amygdala and areas of temporal neocortex.
Conclusions:
Despite similar gaze discrimination abilities, schizophrenia patients exhibit decreased brain activation in areas associated with executive, emotional and visual processing. Controls exhibited increased activation associated with the more difficult task in select frontal and temporal regions. Patients exhibited increased activation associated with direct gaze in temporal regions, which may relate to common symptoms.
