The major symptom dimensions of obsessive-compulsive disorder are mediated by partially distinct neural systems

Abstract

Obsessive-compulsive disorder (OCD) is a clinically heterogeneous disorder characterized by multiple, temporally stable symptom dimensions. Preliminary functional neuroimaging studies suggest that these symptom dimensions may have distinct neural substrates. Whole-brain voxel-based morphometry was used to examine the common and distinct neuroanatomical (structural) substrates of the major symptom dimensions of OCD. First, we compared 55 medication-free patients with OCD and 50 age-matched healthy control subjects. Multiple regression analyses were then used to examine the relationship between global and regional grey matter (GM) and white matter (WM) volumes and symptom dimension scores within the patient group. OCD patients showed decreased GM volume in left lateral orbitofrontal (BA47), left inferior frontal (BA44/45), left dorsolateral prefrontal (BA9) and right medial prefrontal (BA10) cortices and decreased bilateral prefrontal WM volume. Scores on the 'symmetry/ordering' dimension were negatively correlated with 'global' GM and WM volumes. Scores on the 'contamination/washing' dimension were negatively correlated with 'regional' GM volume in bilateral caudate nucleus and WM volume in right parietal region. Scores on the 'harm/checking' dimension were negatively correlated with regional GM and WM volume in bilateral temporal lobes. Scores on the 'symmetry/ordering' dimension were negatively correlated with regional GM volume in right motor cortex, left insula and left parietal cortex and positively correlated with bilateral temporal GM and WM volume. The results remained significant after controlling for age, sex, educational level, overall illness severity, global WM and GM volumes and excluding patients with comorbid depression. The reported symptom dimension-specific GM and WM alterations support the hypothesis that OCD is an etiologically heterogeneous disorder, with both overlapping and distinct neural correlates across symptom dimensions. These results have clear implications for the current neuroanatomical model of OCD and call for a substantial revision of such model which takes into account the heterogeneity of the disorder.

Gray Matter Alterations in Obsessive–Compulsive Disorder: An Anatomic Likelihood Estimation Meta-Analysis

“…Impairments in executive functions, such as planning, have been described in OCD patients. These deficits were associated with decreased activation in this cortical area when compared with HC ( Van den Heuvel et al, 2005). Smaller GMD found in the supramarginal gyrus, a part of the parietal cortex, is consistent with diffusion tensor imaging studies (Menzies et al, 2008b) that showed white matter abnormalities in this brain region and with functional imaging studies that showed a negative relationship between regional cerebral blood flow and symptom intensity (McGuire et al, 1994).…”

“…These studies included 343 OCD patients (80 children and 263 adults) and 318 HC (69 children and 249 adults) (Pujol et al, 2004;Valente et al, 2005, Carmona et al, 2007Christian et al, 2008;Szeszko et al, 2008;Gilbert et al, 2008a, b;Yoo et al, 2008;Lázaro et al, 2009;Van den Heuvel et al, 2009). Study selection was performed by one author (J-YR) and independently verified by another (NL).…”

Correlation between Morphologic Changes and Autism Spectrum Tendency in Obsessive-Compulsive Disorder

“…Previous studies have reported GM reduction in OCD in several regions and commonly in the frontal areas, 9,22 which were consistent with our result. On the other hand, we did not find altered volume in the basal ganglia or anterior cingulate, which has often been reported.…”

Electrophysiology of facilitation priming in obsessive–compulsive and panic disorders

“…Enright, Claridge, Beech, & Kemp-Wheeler, 1994;Hartston & Swerdlow, 1999;Nedeljkovic, et al, 2009). We are not aware of any previous ERP studies to compare OCD subtypes, however previous neuroimaging studies also report distinct patterns of brain activation in participants with washing/ checking/ hoarding profiles (van den Heuvel et al, 2009). …”