Cervical dystonia (CD) is a movement disorder characterized by involuntary muscle contractions of the neck, leading to abnormal head postures and movement, pain and impaired motor function. Current treatments for CD, such as botulinum toxin injections and physical therapy, may not always provide sufficient relief of symptoms and may fail to offer long-term benefits for patients. As a result, new therapeutic approaches are needed. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that modulates neuronal activity. Recent neurophysiological studies suggest that cerebellar tDCS (ctDCS), in particular, could be beneficial in modulating the activity of the sensorimotor network in CD. This clinical trial aims to investigate the effects of ctDCS on the excitability of the sensorimotor network and motor symptom severity in CD patients. Applying transcranial magnetic stimulation (TMS) we will evaluate the effects of anodal, cathodal and sham ctDCS to improve the understanding of the neurophysiological mechanisms underlying CD and the potential therapeutic role of ctDCS.