1 Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
2 Neuroscience and Mental Health Research Institute, Division of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, Wales, United Kingdom.
3 Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands.
4 Department of Neurology, Elisabeth-TweeSteden Ziekenhuis, Tilburg, the Netherlands.
5 Department of Neurology, A.Z. Sint-Jan Brugge-Oostende AV, Bruges, Belgium.
6 Department of Neurology, Ghent University Hospital, Ghent, Belgium.