1. Department of Neuropharmacology, Glaxo Group Research, Ware, Hertfordsire SG12 ODP
2. Glaxo Unit of Behavioural Psychopharmacology, Department of Biosciences, University of Hertfordshire, College Lane, Hatfield, Hertfordshire AL10 9AB
3. Glaxo Institute of Applied Pharmacology, Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QJ, UK