1. Centro Studi e Ricerche in Psichiatria, Piazza del Donatore di Sangue 3, 10154 Torino, Italy
2. Centre for Behavioural Medicine, The School of Pharmacy, University of London, Mezzanine Floor, BMA House, Tavistock Square, London WC1H 9JP, UK
3. Department of Psychology, University of Pavia, Piazza Botta 6, I-27100 Pavia, Italy
4. Centre for Behavioural Medicine, The School of Pharmacy, University of London, Mezzanine Floor, BMA House, Tavistock Square, London WC1H 9JP, UK,