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

  • Jonna Nilsson (a1), Alan J. Thomas (a1), John T. O'Brien (a2) and Peter Gallagher (a3)


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)


Corresponding author

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:


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

  • Jonna Nilsson (a1), Alan J. Thomas (a1), John T. O'Brien (a2) and Peter Gallagher (a3)


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