1. Wellcome Department of Imaging Neuroscience, University College London, London WC1N 3BG, UK.
2. Department of Cortical Function Disorders, National Center of Neurology and Psychiatry, Tokyo 187-8502, Japan.
3. Human Brain Research Center, Kyoto University, Kyoto 606-8507, Japan.
4. Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany.
5. Centre for Functional Magnetic Resonance Imaging of the Brain, University of Oxford, Oxford 0X3 9DU, UK.