1. Institute of Psychiatry, De Crespigny Park; King's College London; London SE5 8AF UK
2. Imanova Ltd.; Hammersmith Hospital; Du Cane Road London W12 0NN UK
3. Department of Pharmacy and Pharmacology; University of Bath; Bath BA2 7AY UK
4. Imaging; Merck Research Laboratories; West Point PA 19486 USA
5. Division of Imaging Sciences and Biomedical Engineering, King's College London; The Rayne Institute, St Thomas' Hospital; London SE1 7EH UK