Diagnostic specificity of the insular cortex abnormalities in first-episode psychotic disorders.
Volume reductions of the insular cortex have been described in schizophrenia, but it remains unclear whether other psychotic disorders such as affective psychosis also exhibit insular cortex abnormalities. In this study, we used magnetic resonance imaging to investigate the gray matter volume of the anterior (short) and posterior (long) insular cortices in 162 first-episode patients with various psychotic disorders (46 schizophrenia, 57 schizophreniform disorder, 34 affective psychosis, and 25 other psychoses) and 62 age- and gender-matched healthy comparison subjects. Patients with schizophrenia showed bilateral volume reduction of the anterior and posterior insular cortices compared with controls, but the remaining first-episode psychosis subgroups had normal insular volumes. The volumes of these insular subregions were significantly smaller in schizophrenia patients than in patients with schizophreniform disorder or affective psychoses. There was no association between the insular cortex volume and daily dosage or type of antipsychotic medication in any patient group. These findings suggest that the widespread volume reduction of the insular cortex is specific to established schizophrenia, implicating its role in the neurobiology of clinical characteristics associated with schizophrenia.
Takahashi
Tsutomu
T
Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne and Melbourne Health, Victoria, Australia. tsutomu@med.u-toyama.ac.jp
Wood
Stephen J
SJ
Soulsby
Bridget
B
Tanino
Ryoichiro
R
Wong
Michael T H
MT
McGorry
Patrick D
PD
Suzuki
Michio
M
Velakoulis
Dennis
D
Pantelis
Christos
C
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000002:abnormalities* / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011618:Psychotic Disorders / Q000175:diagnosis*; D055815:Young Adult