Understanding deep brain stimulation in obsessive compulsive disorder: A preclinical study into the mechanism of action and behaviour

We see a strong impact of deep brain stimulation (DBS) on several aspects of OCD (obsessive compulsive disorder). DBS in different brain areas affects compulsive behaviour, conditioned and unconditioned anxiety. DBS in the internal capsule (IC) shows the most promising behavioural results by uniquely reducing conditioned anxiety and by shortening the compulsive grooming bout in the sapap3 mutant mouse. This suggests that the IC is possibly the best target for DBS in relation to OCD. Further research into the stimulation of the IC has to clarify which changes in cellular or system level are responsible for these behavioural effects. The behavioural relevance of the effect of DBS in the nucleus accumbens (NAc) core on the monoamines in the prefrontal cortex (PFC) is as of yet unclear. Further behavioural experiments combined with microdialysis have to be performed to investigate a possible link between the increase in PFC monoamines and locomotor behaviour during DBS in the NAc core. DBS is widely used in clinical settings for several different diseases. However, the lack of knowledge of the optimal target for DBS, the neurobiological mechanisms underlying the rapid effects of DBS and the specific impact of DBS on the different symptoms of the diseases prevents the full potential of its application. This thesis could be viewed as one of the building blocks to achieve this.