**6. Conclusion**

Ethics in the history of psychosurgery has played a secondary role in experimentation due to the lack of effective medical therapy for mental disorders. The highest ethical standards for the use of DBS should be applied. The great suffering of patients and their poor quality of life, as well as the high social costs, are in favor of the use of this method in patients resistant to pharmacological therapy. Some fundamental ethical problems are mostly extendable to all clinical interventions as well as to neurostimulation procedures in neurological and psychiatric disorders. The reversibility of the method and the potential benefits are important ethical arguments for the use of DBS in addiction. On the other hand, DBS is not free of risks (hemorrhages, infections, battery life), so every patient has to be carefully evaluated, and precise ethical standards must be defined in the form of inclusion and exclusion criteria. Beyond the negative parabola of psychosurgery, a rational scientific solid, a precise experimental protocol and adherence to a rigid ethical code are key factors to ensure the success of these researches. As to the target, the nucleus accumbens is very promising. We must keep in mind when choosing new optimal neural targets that likely the local and surrounding DBS influences might depend on the stimulated structure and its specific afferents, efferents, cell types, ratio of projection neurons to interneurons and transmitter systems.
