Altered fronto-striatal fiber topography and connectivity in obsessive-compulsive disorder.
Fronto-striatal circuits are hypothesized to be involved in the pathophysiology of obsessive-compulsive disorder (OCD). Within this circuitry, ventral frontal regions project fibers to the ventral striatum (VS) and dorsal frontal regions to the dorsal striatum. Resting state fMRI research has shown higher functional connectivity between the orbitofrontal cortex (OFC) and the dorsal part of the VS in OCD patients compared to healthy controls (HC). Therefore, we hypothesized that in OCD the OFC predominantly project fibers to the more dorsal part of the VS, and that the structural connectivity between the OFC and VS is higher compared to HC. A total of 20 non-medicated OCD patients and 20 HC underwent diffusion-weighted imaging. Connectivity-based parcellation analyses were performed with the striatum as seed region and the OFC, dorsolateral prefrontal cortex, and dorsal anterior cingulate cortex as target regions. Obtained connectivity maps for each frontal region of interest (ROI) were normalized into standard space, and Z-component (dorsal-ventral) coordinate of center-of-gravity (COG) were compared between two groups. Probabilistic tractography was performed to investigate diffusion indices of fibers between the striatum and frontal ROIs. COG Z-component coordinates of connectivity maps for OFC ROI were located in the more dorsal part of the VS in OCD patients compared to HC. Fractional anisotropy of fibers between the OFC and the striatum was higher in OCD patients compared to HC. Part of the pathophysiology of OCD might be understood by altered topography and structural connectivity of fibers between the OFC and the striatum.
Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; Computational Neuroscience Laboratories, Advanced Telecommunications Research Institute International, Kyoto, Japan.
Takashi
T
Nakamae
Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; Computational Neuroscience Laboratories, Advanced Telecommunications Research Institute International, Kyoto, Japan.
Yuki
Y
Sakai
Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Yoshinari
Y
Abe
Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Seiji
S
Nishida
Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Kenji
K
Fukui
Department of Radiology, Graduate School of Medical Science Kyoto Prefectural University of Medicine, Kyoto, Japan.
Kei
K
Yamada
Department of Psychiatry, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Manabu
M
Kubota
Department of Neuropsychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands; The Netherlands Institute for Neuroscience, an institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands.
Damiaan
D
Denys
Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; Computational Neuroscience Laboratories, Advanced Telecommunications Research Institute International, Kyoto, Japan.
Jin
J
Narumoto
D000328:Adult; D001921:Brain / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000503:physiopathology*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D012044:Regression Analysis; D066328:Ventral Striatum / Q000503:physiopathology*