J Psychiatry Neurosci 2009; 34(6): 443-449
Geumsook Shim, MD; Wi Hoon Jung, MS; Jung-Seok Choi, MD; Myung Hun Jung, MD; Joon Hwan Jang, MD; Ji-Young Park, MS; Chi-Hoon Choi, MD, PhD; Do-Hyung Kang, MD, PhD; Jun Soo Kwon, MD, PhD
Shim, J.S. Choi, M.H. Jung, Jang, Kang, Kwon — Department of Psychiatry, Seoul National University College of Medicine; W.H. Jung, Park, Kwon — Neuroscience Institute, SNU-MRC; C.H. Choi — Department of Radiology, National Medical Center, Seoul, Korea
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.
Limitations: 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.
Submitted Mar. 10, 2009; Revised Jul. 4, 2009; Accepted Jul. 8, 2009.
Acknowledgements: This work was supported by Cognitive Neuroscience Program of the Korean Ministry of Science and Technology (M10644020003-08N4402-00310).
Competing interests: None declared.
Contributors: Drs. Shim, Kang and Kwon designed the study. Mr. W.H. Jung, Ms. Park and Drs. J.S. Choi, M.H. Jung, Jang, C.H. Choi and Kang acquired the data, which Dr. Shim, Mr. W.H. Jung and Ms. Park analyzed. Dr. Shim wrote the article, which all other authors reviewed. All authors gave final approval for publication.
Correspondence to: Dr. J.S. Kwon, Brain & Cognitive Sciences-WCU program, College of Natural Sciences, Seoul National University and Department of Psychiatry, Seoul National University College of Medicine, 101 Daehak-no, Chongno-gu, Seoul, Korea, 110-744; fax 82-2-747-9063; email@example.com