[1] Univ Aachen, Sch Med, Dept Neurol, D-52057 Aachen, Germany
[2] Univ Aachen, Sch Med, Dept Phoniatr, D-52057 Aachen, Germany
[3] Univ Aachen, Sch Med, Dept Pediat Audiol, D-52057 Aachen, Germany
[4] Univ Aachen, Sch Med, Dept Commun Disorders, D-52057 Aachen, Germany
[5] Kliniken Schmieder Allensbach Hegau Klinikum, Dept Neurol, Singen, Germany