1. Department of Neuroradiology, University Medical Center, Georg-August University, Göttingen, Germany
2. MR-Research in Neurology and Psychiatry, University Medical Center, Georg-August University, Göttingen, Germany
3. Division of Sports Medicine, Department of Internal Medicine, University Medical Center, Ruprecht-Karls University, Heidelberg, Germany
4. Department of Neuroradiology, University Medical Centre, Friedrich-Alexander University, Erlangen, Germany
5. Department of Neurology, University Medical Centre, Friedrich-Alexander University, Erlangen, Germany
6. Department of Physiology, Hypoxia Research Unit, University of Glamorgan, Pontypridd, South Wales, UK