Differences in neuropsychological performance between subtypes of obsessive-compulsive disorder.
OBJECTIVE
Neuropsychological studies have suggested that frontal-striatal dysfunction plays a role in obsessive-compulsive disorder (OCD), although findings have been inconsistent, possibly due to heterogeneity within the disorder and methodological issues. The purpose of the present study was therefore to compare the neuropsychological performance of different subtypes of OCD and matched non-clinical controls (NCs) on the Cambridge Automated Neuropsychological Test Battery (CANTAB).


METHODS
Fifty-nine OCD patients and 59 non-clinical controls completed selected tests from CANTAB examining executive function, visual memory and attentional-set shifting. Depression, anxiety and OCD symptoms were also assessed.


RESULTS
From 59 OCD patients, four subtypes were identified: (i) washers; (ii) checkers; (iii) obsessionals; and (iv) mixed symptom profile. Comparisons between washers, checkers, obsessionals and NCs indicated few differences, although checkers were generally found to exhibit poorer performance on spatial working memory, while obsessionals performed poorly on the spatial recognition task. Both checkers and the mixed subgroups showed slowed initial movement on the Stockings of Cambridge planning task and poorer pattern recognition relative to NCs.


CONCLUSIONS
Overall the results suggested greater impairments in performance on neuropsychological tasks in checkers relative to other subtypes, although the observed effects were small and the conclusions limited by the small subtype samples. Future research will need to account for factors that influence neuropsychological performance in OCD subtypes.
Nedeljkovic
Maja
M
SwinPsyCHE Research Centre, Faculty of Life and Social Sciences, Swinburne University of Technology, Hawthorn, Australia. mnedeljkovic@swin.edu.au
Kyrios
Michael
M
Moulding
Richard
R
Doron
Guy
G
Wainwright
Kylie
K
Pantelis
Chris
C
Purcell
Rosemary
R
Maruff
Paul
P
D000328:Adult; D001288:Attention / Q000502:physiology; D003072:Cognition Disorders / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D003342:Corpus Striatum / Q000503:physiopathology; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D007206:Individuality; D008297:Male; D008569:Memory Disorders / Q000145:classification / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D009771:Obsessive-Compulsive Disorder / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D009949:Orientation / Q000502:physiology; D011340:Problem Solving / Q000502:physiology; D011594:Psychometrics; D011597:Psychomotor Performance / Q000502:physiology