Susana Muoz Maniega1, Lars Penke2,
Mara C. Valds Hernndez1, Catherine Murray2, Natalie
A. Royle1, Alan J. Gow2, Jonathan D. Clayden3,
John M. Starr4, Mark E. Bastin5, Ian J. Deary2,
Joanna M. Wardlaw1
1Clinical Neurosciences, University of
Edinburgh, Edinburgh, United Kingdom; 2Psychology, University of
Edinburgh, Edinburgh, United Kingdom; 3Institute of Child Health,
University College London, London, United Kingdom; 4Geriatric
Medicine, University of Edinburgh, Edinburgh, United Kingdom; 5Medical
Physics, University of Edinburgh, Edinburgh, United Kingdom
Using
diffusion MRI tractography we segmented white matter tracts thought to be
related with cognition in a cohort of healthy older people. We registered the
tract segmentations to parametric maps of magnetization ratios and T1
relaxation times and used these parameters, as well as fractional anisotropy
and mean diffusivity, to characterise the white matter integrity of the
tracts. The study of how tract integrity relates to cognition in old age
revealed new relationships not shown by diffusion parameters only. This work
suggests that a multi-parameter approach could unravel the effects of ageing
on the brain and cognition better than the lone use of diffusion MRI.
Keywords