Deficit in Gender Discrimination Related Circuit in Nonaffected Siblings of Schizophrenia Patients : Preliminary Functional MRI Study

Choi, Kyeong Sook; Jeong, Bumseok; Kim, Ji Woong; Choi, Jeewook

Abstract

OBJECTIVES
: A neural circuit including amygdala, the hippocampal complex and prefrontal cortex was associated with deficits in facial processing in schizophrenia. These deficits have a significant impact on social functioning in schizophrenia. Both neuropsychological deficits and brain structural abnormalities in first-degree relatives of schizophrenia patients suggest that they may also have the deficit in facial information processing as genetic factors. The purpose of this study was to explore the dysfunction of facial information processing in first-degree relatives of schizophrenia patients using functional magnetic neuroimaging (fMRI).
METHODS
: Ten non-affected siblings of schizophrenic patients and 10 normal comparison subjects having no schizophrenic siblings underwent fMRI during the d ynamic facial change procedure consisting of presentations of facial emotion and gender discrimination stimuli. The emotion discrimination condition consisted of the presentation of 12 happy faces and 12 disgust/fear faces. The gender discrimination condition consisted of the presentation of 12 male faces and 12 female faces. Condition-specific brain activations were compared between non-affected siblings and normal comparison subjects
RESULTS
: The facial information processing related brain regions including fusiform gyrus, several areas of frontal, temporal, occipital, and cerebellar regions exhibited more activation during gender discrimination than emotion discrimination tasks in each group. During gender discrimination task, siblings of schizophrenic patients showed less activation in right fusiform gyrus, both middle and superior frontal gyrus, left cuneus, and left inferior frontal gyrus, compared with normal comparison subjects.
CONCLUSION
: Dysfunctional facial information processing, such as a deficit in gender discrimination, might be an endophenotype of schizophrenia.