1. Department of Psychology, Center for Lifespan Changes in Brain and Cognition, University of Oslo, Oslo, Norway
2. Department of Biomedicine, Faculty of Medicine, University of Barcelona, Barcelona, Spain
3. Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
4. Centre for Old Age Psychiatric Research, Innlandet Hospital Trust, Ottestad, Norway
5. Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
6. Department of Geriatric Medicine, Oslo University Hospital, Oslo, Norway
7. Norwegian National Advisory Unit on Ageing and Health, Vestfold Hospital Trust, Tønsberg, Norway
8. Department of Neurology, Oslo University Hospital, Oslo, Norway
9. Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
10. Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
11. Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK