1. Department of Radiology; University Medical Center Utrecht; Utrecht The Netherlands
2. Philips Technologie GmbH, Innovative Technologies; Research Laboratories; Hamburg Germany
3. Institute of Biomedical Engineering Department of Engineering Science; University of Oxford; Oxford UK
4. Centre for Functional Magnetic Resonance Imaging of the Brain; Nuffield Department of Clinical Neurosciences, University of Oxford; Oxford UK
5. C.J. Gorter Center for High Field MRI Department of Radiology; Leiden University Medical Center; Leiden The Netherlands