Electrical deep neuromodulation in psychiatry

Addressing treatment refractoriness in psychiatric diseases is an essential public health objective. The last two decades have seen an increasing interest for deep brain stimulation (DBS) of several brain targets. In this chapter, we have reviewed the main DBS clinical trials in psychiatric diseases, mainly obsessive compulsive disorders (OCD) and depression, but also emerging research in other psychiatric disorders. While its efficacy and safety are confirmed, DBS is still not considered as standard therapy in psychiatry. However, advances in neuroimaging research combined to behavioral and electrophysiological data uniquely provided by DBS studies improve knowledge on physiopathology in these brain diseases. This will help define the optimal brain targets according to specific phenotype dimensions. Revealing the mechanisms of action and effects of DBS will support that its impact goes beyond a loco-regional brain stimulation and confirms that electrical neuromodulation influences brain networks. Added to the progress in neuromodulation technology, these insights will hopefully facilitate a more widespread application of this promising treatment. Future development of a personalized multimodal assessment of underlying dysfunctional brain networks will open new circuit-specific treatment perspectives that may facilitate better patient outcomes.