[1] Kings Coll London, Div Psychol Med, Inst Psychiat, London SE5 8AF, England
[2] Kings Coll London, MRC, Social Genet & Dev Psychiat Res Ctr, London SE5 8AF, England
[3] Imperial Coll Healthcare NHS Trust, Radiol Sci Unit, London, England
[4] Imperial Coll Healthcare NHS Trust, Dept Nucl Med, London, England
[5] Imperial Coll Sch Med, MRI Unit, MRC Clin Sci Ctr, Hammersmith Hosp, London, England