1. Danish Headache Center and Department of NeurologyRigshospitalet Glostrup, Faculty of Health and Medical Sciences, University of CopenhagenGlostrup Denmark
2. Visual Processing Laboratory, Ophthalmic DepartmentOtto von Guericke UniversityMagdeburg Germany
3. Functional Imaging Unit, Department of Clinical PhysiologyNuclear Medicine and PET Rigshospitalet Glostrup, Faculty of Health and Medical Sciences, University of CopenhagenGlostrup Denmark
4. Center for Behavioral Brain SciencesMagdeburg Germany