Cognitive control in childhood-onset obsessive-compulsive disorder: a functional MRI study.
BACKGROUND
Failure to resist chronic obsessive-compulsive symptoms may denote an altered state of cognitive control. We searched for the cerebral regions engaged in this dysfunction.


METHODS
Differences in brain regional activity were examined by event-related functional magnetic regional imaging (fMRI) in a group of adolescents or young adults (n = 12) with childhood-onset obsessive-compulsive disorder (OCD), relative to healthy subjects. Subjects performed a conflict task involving the presentation of two consecutive and possibly conflicting prime and target numbers. Patients' image dataset was further analysed according to resistance or non-resistance to symptoms during the scans.


RESULTS
Using volume correction based on a priori hypotheses, an exploratory analysis revealed that, within the prime-target repetition condition, the OCD subjects activated more than healthy subjects a subregion of the anterior cingulate gyrus and the left parietal lobe. Furthermore, compared with 'resistant' patients, the 'non-resistant' OCD subjects activated a bilateral network including the precuneus, pulvinar and paracentral lobules.


CONCLUSIONS
Higher regional activations suggest an abnormal amplification process in OCD subjects during the discrimination of repetitive visual stimuli. The regional distribution of functional changes may vary with the patients' ability to resist obsessions.
Viard
Armelle
A
INSERM-CEA ERM 02-05, 'Neuroimaging in psychiatry', IFR49, Service Hospitalier Frédéric Joliot, Orsay, France.
Flament
Martine F
MF
Artiges
Eric
E
Dehaene
Stanislas
S
Naccache
Lionel
L
Cohen
David
D
Mazet
Philippe
P
Mouren
Marie-Christine
MC
Martinot
Jean-Luc
JL
D000328:Adult; D017668:Age of Onset; D001921:Brain / Q000473:pathology; D002648:Child; D003072:Cognition Disorders; D003220:Conflict, Psychological; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000473:pathology* / Q000523:psychology*; D013647:Task Performance and Analysis