Dystonia is a severe movement disorder involving increased muscular activity and can be very variable. To date, the treatment of dystonia is challenging. One effective therapy is deep brain stimulation (DBS), an invasive therapy, where stimulation electrodes are inserted in deep brain regions and a continuous electrical therapy is delivered via a pacemaker. However, the optimization of the therapy is a long process, up to months and there is no immediate adaptation to different disease states. This project aims to improve DBS therapy: The first aim is to learn more about electrical brain activity that could be the feedback signal for individualized therapy. Secondly, the investigators want to gather information about the long-term development of the signal and potential hints for optimal therapy locations that could be acutely used to accelerate therapy optimization. To date, recordings mainly in lab settings, have suggested low-frequency activity as a biomarker for dystonia. Biomarkers are signals that are changed with therapy and that reflect symptom severity. Further understanding of the low-frequency biomarker for dystonia and its applicability in everyday life is one of the objectives in this study. Therefore, using a pacemaker that can also record brain activity, biomarker activity will be recorded for 12 months. At the same time, development of clinical symptoms will be assessed using an application with weekly questionnaires on symptoms and a video diary. At monthly appointments for data saving, resting state as well as motor activity during a finger tapping task will be recorded to also assess the development of side-effects, such as stimulation-induced slowing, and their biomarkers.