Article

Role of medial cortical networks for anticipatory processing in obsessive-compulsive disorder

Department of Radiology, MGH/MIT/HMS A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and McLean Hospital, Harvard Medical School, Charlestown, Massachusetts, USA.
Human Brain Mapping (Impact Factor: 6.92). 09/2012; 33(9):2125-34. DOI: 10.1002/hbm.21341
Source: PubMed

ABSTRACT Recurrent anticipation of ominous events is central to obsessions, the core symptom of obsessive-compulsive disorder (OCD), yet the neural basis of intrinsic anticipatory processing in OCD is unknown. We studied nonmedicated adults with OCD and case matched healthy controls in a visual-spatial working memory task with distractor. Magnetoencephalography was used to examine the medial cortex activity during anticipation of to-be-inhibited distractors and to-be-facilitated retrieval stimuli. In OCD anticipatory activation to distractors was abnormally reduced within the posterior cingulate and fusiform gyrus compared to prominent activation in controls. Conversely, OCD subjects displayed significantly increased activation to retrieval stimuli within the anterior cingulate and supplementary motor cortex. This previously unreported discordant pattern of medial anticipatory activation in OCD was accompanied by normal performance accuracy. While increased anterior cortex activation in OCD is commonly viewed as failure of inhibition, the current pattern of data implicates the operation of an anterior compensatory mechanism amending the posterior medial self-regulatory networks disrupted in OCD.

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    • "In addition, two studies have revealed less grey matter in regions within the occipital cortices in adult OCD patients [Szeszko et al., 2008; Togao et al., 2010] and structural abnormalities of the splenium have also been identified suggesting abnormal physical connectivity in posterior brain regions including the occipital lobes [Park et al., 2011]. Moreover, the supplementary motor cortex is implicated in aspects of cognitive control such as conflict monitoring [Garavan et al. 2003; Hester et al. 2004]; and recent functional imaging studies have reported abnormalities of the supplementary motor area and pre-supplementary motor area in adult patients with OCD [Ciesielski et al., 2012; Woon et al., 2012]. The supplementary motor area has been shown to be an effective target area for repetitive transcranial magnetic stimulation in the treatment of OCD [Jaafari et al., 2012; Kumar and Chadda, 2011]. "
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    ABSTRACT: Obsessive-compulsive disorder (OCD) is an often severely disabling illness with onset generally in childhood or adolescence. Little is known, however, regarding the pattern of brain resting state activity in OCD early in the course of illness. We therefore examined differences in brain resting state activity in patients with pediatric OCD compared with healthy volunteers and their clinical correlates. Twenty-three pediatric OCD patients and 23 healthy volunteers (age range 9-17), matched for sex, age, handedness, and IQ completed a resting state functional magnetic resonance imaging exam at 3T. Patients completed the Children's Yale Brown Obsessive Scale. Data were decomposed into 36 functional networks using spatial group independent component analysis (ICA) and logistic regression was used to identify the components that yielded maximum group separation. Using ICA we identified three components that maximally separated the groups: a middle frontal/dorsal anterior cingulate network, an anterior/posterior cingulate network, and a visual network yielding an overall group classification of 76.1% (sensitivity = 78.3% and specificity = 73.9%). Independent component expression scores were significantly higher in patients compared with healthy volunteers in the middle frontal/dorsal anterior cingulate and the anterior/posterior cingulate networks, but lower in patients within the visual network. Higher expression scores in the anterior/posterior cingulate network correlated with greater severity of compulsions among patients. These findings implicate resting state fMRI abnormalities within the cingulate cortex and related control regions in the pathogenesis and phenomenology of OCD early in the course of the disorder and prior to extensive pharmacologic intervention. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.
    Human Brain Mapping 10/2014; 35(10). DOI:10.1002/hbm.22551 · 6.92 Impact Factor
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    • "In addition, two studies have revealed less grey matter in regions within the occipital cortices in adult OCD patients [Szeszko et al., 2008; Togao et al., 2010] and structural abnormalities of the splenium have also been identified suggesting abnormal physical connectivity in posterior brain regions including the occipital lobes [Park et al., 2011]. Moreover, the supplementary motor cortex is implicated in aspects of cognitive control such as conflict monitoring [Garavan et al. 2003; Hester et al. 2004]; and recent functional imaging studies have reported abnormalities of the supplementary motor area and pre-supplementary motor area in adult patients with OCD [Ciesielski et al., 2012; Woon et al., 2012]. The supplementary motor area has been shown to be an effective target area for repetitive transcranial magnetic stimulation in the treatment of OCD [Jaafari et al., 2012; Kumar and Chadda, 2011]. "
    Proc. Intl. Soc. Mag. Reson. Med., p. 3131, Melbourne; 01/2012
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