Patients with obsessive-compulsive disorder (OCD) with the compulsion to wash have fear of contamination or feel contaminated. The compulsion to wash often lasts for hours, so that massive difficulties to cope with everyday life follow. There exist only few data on the aetiology of specific OCD-subgroups as the compulsive disorder to wash. Specific neural correlates of OCD with compulsion to wash have never been analyzed before. Existing neuroimaging data on OCD generally show changes of neural activity in the striatum, orbitofrontal cortex and anterior cingulated gyrus. A dysfunction of frontostriatal loops is supposed as one cause of OCD. From a psychoanalytic point of view OCD with the specific compulsion to wash is related to a suppression of autosexual and aggressive drives.

In our neuroimaging study (fMRI) we compared the neural networks of OCD-patients with the compulsion to wash and healthy controls. We used a picture-paradigm consisting of autosexual, aggressive, disgusting, neutral and water pictures. We were interested in the neural correlates of OCD-patients with compulsion to wash regarding the different affective pictures categories and expected neural differences between patients and controls. Stimuli were taken partly from the IAPS, partly also self- constructed and validated by a control group. First results point at significant differences in neural activity between patients and healthy controls, especially in diseases-related components as autosexual, aggressive and water pictures. OCD-patients used a more extended and more emotional related network of brain structures.

Our study provides new insights into neural correlates of OCD-patients with the compulsion to wash.