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White Matter and Cognitive Decline in Aging: A Focus on Processing Speed and Variability

Published online by Cambridge University Press:  17 February 2014

Jonna Nilsson
Institute of Ageing and Health, Newcastle University, United Kingdom
Alan J. Thomas
Institute of Ageing and Health, Newcastle University, United Kingdom
John T. O'Brien
Department of Psychiatry, University of Cambridge, Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, United Kingdom
Peter Gallagher*
Institute of Neuroscience, Newcastle University, United Kingdom
Correspondence and reprint requests to: Peter Gallagher, Institute of Neuroscience, Newcastle University, The Henry Wellcome Building, Framlington Place, Newcastle upon Tyne, NE2 4HH UK. E-mail:


White matter (WM) change plays an important role in age-related cognitive decline. In this review, we consider methodological advances with particular relevance to the role of WM in age-related changes in processing speed. In this context, intra-individual variability in processing speed performance has emerged as a sensitive proxy of cognitive and neurological decline while neuroimaging techniques used to assess WM change have become increasingly more sensitive. Together with a carefully designed task protocol, we emphasize that the combined implementation of intra-individual variability and neuroimaging techniques hold promise for specifying the WM-processing speed relationship with implications for normative and clinical samples. (JINS, 2014, 20, 1–6)

Short Review
Copyright © The International Neuropsychological Society 2014 

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