The goal of this observational study is to learn about functional neurological disorders in patients with common non-functional movement disorders (functional overlay). The main questions it aims to answer are: * What is the frequency of functional neurological disorders in patients with non-functional movement disorders (functional overlay)? * What are the characteristics of functional neurological disorders in patients with non-functional movement disorders? Participants will be examined clinically and electrophysiologically, the examinations consist of: * a neurological examination * neuropsychological testing * electrophysiological tremor diagnostic * questionnaires about psychological, biological and social risk factors Researchers will compare patients with functional motor disorders to patients wit non-functional movement disorders to see if they differ from each other regarding the functional symptoms.