1. J. B. Brewer, Neuroscience Program and School of Medicine, Stanford University, Stanford, CA 94305, USA. Z. Zhao and J. E. Desmond, Department of Psychology, Stanford University, Stanford, CA 94305, USA. G. H. Glover, Department of Radiology, Stanford University, Stanford, CA 94305, USA. J. D. E. Gabrieli, Department of Psychology and Neuroscience Program, Stanford University, Stanford, CA 94305, USA.