[1] Univ Florence, Neurofarba Dept, Largo Brambilla 3, I-50134 Florence, Italy
[2] Queen Elizabeth Univ Hosp Glasgow, Inst Cardiovasc & Med Sci, Glasgow, Lanark, Scotland
[3] Univ Glasgow, Inst Cardiovasc & Med Sci, Glasgow, Lanark, Scotland
[4] Univ Western Australia, Harry Perkins Inst Med Res, Sch Med & Pharmacol, QEII Med Ctr, Perth, WA, Australia
[5] Univ Glasgow, Inst Cardiovasc & Med Sci, Glasgow, Lanark, Scotland
[6] Univ Edinburgh, Div Neuroimaging Sci JMW, Edinburgh, Midlothian, Scotland