1. Department of Neurology, Medical Faculty, RWTH Aachen University, Aachen, Germany
2. Stotterintensivtherapie Cook, Karlsruhe, Germany
3. Department of Speech-Language Pathology, Monmouth University, West Long Branch, NJ, USA
4. Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany
5. Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Jülich, Germany