Altered corticostriatal functional connectivity in obsessive-compulsive disorder.
BACKGROUND
Neurobiological models of obsessive-compulsive disorder (OCD) emphasize disturbances in the function and connectivity of brain corticostriatal networks, or "loops." Although neuroimaging studies of patients have supported this network model of OCD, very few have applied measurements that are sensitive to brain connectivity features.


OBJECTIVE
Using resting-state functional magnetic resonance imaging, we tested the hypothesis that OCD is associated with disturbances in the functional connectivity of primarily ventral corticostriatal regions, measured from coherent spontaneous fluctuations in the blood oxygenation level-dependent (BOLD) signal.


METHODS
Case-control cross-sectional study.


METHODS
Hospital referral OCD unit and magnetic resonance imaging facility.


METHODS
A total of 21 patients with OCD (10 men, 11 women) and 21 healthy control subjects matched for age, sex, and estimated intelligence.


METHODS
Voxelwise statistical parametric maps testing the strength of functional connectivity of 4 striatal seed regions of interest (dorsal caudate nucleus, ventral caudate/nucleus accumbens, dorsal putamen, and ventral putamen) with remaining brain areas.


RESULTS
For both groups, there was a clear distinction in the pattern of cortical connectivity of dorsal and ventral striatal regions, consistent with the notion of segregated motor, associative, and limbic corticostriatal networks. Between groups, patients with OCD had significantly increased functional connectivity along a ventral corticostriatal axis, implicating the orbitofrontal cortex and surrounding areas. The specific strength of connectivity between the ventral caudate/nucleus accumbens and the anterior orbitofrontal cortex predicted patients' overall symptom severity (r(2) = 0.57; P < .001). Additionally, patients with OCD showed evidence of reduced functional connectivity of the dorsal striatum and lateral prefrontal cortex, and of the ventral striatum with the region of the midbrain ventral tegmental area.


CONCLUSIONS
This study directly supports the hypothesis that OCD is associated with functional alterations of brain corticostriatal networks. Specifically, our findings emphasize abnormal and heightened functional connectivity of ventrolimbic corticostriatal regions in patients with OCD.
Harrison
Ben J
BJ
Institut d'Alta Tecnologia-Parc de Recerca Biomèdica de Barcelona, Centro Radiológico Computerizado Corporació Sanitària, Barcelona, Spain. habj@unimelb.edu.au
Soriano-Mas
Carles
C
Pujol
Jesus
J
Ortiz
Hector
H
López-Solà
Marina
M
Hernández-Ribas
Rosa
R
Deus
Joan
J
Alonso
Pino
P
Yücel
Murat
M
Pantelis
Christos
C
Menchon
José M
JM
Cardoner
Narcís
N
D000328:Adult; D001479:Basal Ganglia / Q000503:physiopathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D002421:Caudate Nucleus / Q000503:physiopathology; D002540:Cerebral Cortex / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data*; D008297:Male; D008959:Models, Neurological; D009434:Neural Pathways / Q000503:physiopathology*; D009714:Nucleus Accumbens / Q000503:physiopathology; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000503:physiopathology
D010100:Oxygen