Neuropsychological profile of childhood-onset obsessive-compulsive disorder

In this review paper, studies focusing on the neuropsychological characteristics of childhood-onset obsessive-compulsive disorder (OCD) were evaluated. Systematic electronic searches were undertaken using MEDLINE and Psycinfo databases (until June 2006). The presented results are of those that focus on the processes of attention, memory, and executive functions related to the aspects ofthe measured instruments used. The aim of this review was to provide a general neuropsychological profile of childhood-onset OCD based on the reviewed studies. In general, results showed that there is no clear evidence that the neuropsychological aspects of childhood-onset OCD differ from those of adult-onset OCD. In parallel with this, the processes of attention and memory in childhood-onset OCD are observed to be selective and biased, and this bias is directed towards threat-relevant stimuli related to obsessions and compulsions. In addition, dysfunction in memory and visuospatial processes in OCD patients do not result from memory impairment per se, but rather from an impaired ability to apply efficiently elaborated memory strategies. In childhood-onset OCD, the various lines of evidence consistently include impairment of response suppression and motor inhibition abilities; there is less consistent evidence for reduced set shifting, fluency, conceptual thinking, and planning ability. Whereas clinical observation suggests that a central problem in OCD is at the meta-memory level and that people with OCD have less meta-cognitive ability, processing of meta-cognition in childhood-onset OCD has not yet been investigated adequately. Finally, the results of the reviewed studies were evaluated in terms of the effects of basic co-morbidity, such as depression, Tourette's disorder, tic disorder, and other confounding variables.