Reduced cortical folding of the anterior cingulate cortex in obsessive-compulsive disorder.
BACKGROUND
Anterior cingulate cortex (ACC) abnormalities have been implicated consistently in the pathophysiology of obsessive-compulsive disorder (OCD), yet it remains unclear whether these abnormalities originated during early neurodevelopment. In this study, we examined the ACC sulcal/gyral patterns to investigate whether neurodevelopmental anomalies of the ACC were present in patients with OCD. We hypothesized that patients with OCD would show reduced cortical folding of the ACC compared with controls.


METHODS
We used magnetic resonance imaging (MRI) of 169 healthy volunteers and 110 patients with OCD to examine the paracingulate sulcus and cingulate sulcus. We assessed cortical folding patterns according to established classification criteria and constructed 3 categories of paracingulate sulcus morphology according to its presence and anteroposterior extent: "prominent," "present" and "absent." We classified the cingulate sulcus as "interrupted" or "continuous" according to the interruptions in its course. In addition, we evaluated ACC sulcal asymmetry based on interhemispheric comparisons of paracingulate sulcus morphology.


RESULTS
Analyses revealed that patients with OCD were significantly less likely than controls to show a well-developed left paracingulate sulcus: 50.0% of patients and 65.1% of controls showed a "prominent" or "present" paracingulate sulcus in the left hemisphere. However, there were no differences in regard to cingulate sulcus continuity, and patients also showed the same leftward ACC sulcal asymmetry as controls.


CONCLUSIONS
Our study was limited by the fact that we obtained the MRI scans from 2 different scanners, and we did not calculate cerebral fissurization as our study was restricted to 1 specific brain region. Moreover, patients and controls differed significantly in terms of sex ratio and IQ, although we controlled these variables as covariates.


CONCLUSIONS
Our findings imply a subtle deviation in the early neurodevelopment of the ACC in patients with OCD, but the extent to which these anomalies contributed to the pathogenesis of OCD remains unclear. Further studies that link the ACC morphologic anomalies to the pathophysiology of OCD are recommended.
Shim
Geumsook
G
Department of Psychiatry, Seoul National University College of Medicine, Seoul, Korea.
Jung
Wi Hoon
WH
Choi
Jung-Seok
JS
Jung
Myung Hun
MH
Jang
Joon Hwan
JH
Park
Ji-Young
JY
Choi
Chi-Hoon
CH
Kang
Do-Hyung
DH
Kwon
Jun Soo
JS
D000328:Adult; D002540:Cerebral Cortex / Q000473:pathology / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006179:Gyrus Cinguli / Q000473:pathology* / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000473:pathology* / Q000523:psychology; D011569:Psychiatric Status Rating Scales; D055815:Young Adult