1. Headache Unit, Department of Neurology Hospital Clínico Universitario de Valladolid Valladolid Spain
2. Institute for Biomedical Research of Salamanca (IBSAL) Salamanca Spain
3. Headache Unit, Department of Neurology Institute of NeurosciencesHospital Clínico San Carlos, IdISSC Madrid Spain
4. Department of Medicine Universidad Complutense de Madrid Madrid Spain
5. Neurovascular Research Laboratory Instituto de Biología y Genética Molecular, Universidad de Valladolid – Consejo Superior de Investigaciones Científicas Madrid Spain
6. Department of Medicine School of Medicine Universidad de Valladolid Valladolid Spain