This book contains the contributions to the symposium "Functional Mapping of the Brain in Vascular Disorders," held at the Thirteenth World Congress of Neurology, Sep tember 1-6, 1985 in Hamburg, FRG. I have to thank the contributors to this symposium for submitting their manu scripts long before the congress so that the printed procee dings could be distributed to the audience. I hope that this will enable the participants in this symposium not only to recall the vivid presentation of the lectures and the highlights of the discussions, but also to widen their knowlegde of the topics dealt with during the symposium by rereading the chapters on the various issues. I would also like to express my thanks to the company UCB, Kerpen, FRG, who sup ported the symposium and the printing of these proceedings. W. -D. HEISS Cologne, July 1985 Contents The Purpose of Functional Mapping in Focal Cerebral Ischemia W. -D. Heiss . . . . . . . . . . . . . . . . . . . . . . 1 Positron Emission Tomography Versus Nuclear Magnetic Resonance Imaging? M. M. Ter-Pogossian (With 1 Figure) . . . . 5 Aims on Phosphorus-3l Magnetic Resonance Imaging K. Kogure, H. Ohtomo, S. Matsui, and H. Kohno (With 10 Figures) . . . . . . . . . . . . . . . . . 15 In Vivo Nuclear Magnetic Resonance Imaging of Sodium-23 in the Human Head S. K. Hilal, A. A. Maudsley, J. B. Ra, H. E. Simon, P. Roschmann, S. Wittekoek, Z. H. Cho, and S. K. Mun (With 5 Figures) . . . . . . . . . . . . . . . . . 29 Uncoupling of Flow and Metabolism in Infarcted Tissue T. Jones, R. J. S. Wise, R. S. J. Frackowiak, J. M."