Hamied Ahmad Haroon1,2,
Heather Reynolds1, Stephen F. Carter2,3, Karl V.
Embleton2,4, Karl G. Herholz2,3, Geoff J. Parker1,2
1Imaging
Science & Biomedical Engineering, School of Cancer & Enabling
Sciences, The University of Manchester, Manchester, England, United Kingdom; 2Biomedical
Imaging Institute, The University of Manchester, Manchester, England, United
Kingdom; 3Wolfson Molecular Imaging Centre, School of Cancer &
Enabling Sciences, The University of Manchester, Manchester, England, United
Kingdom; 4School of Psychological Sciences, The University of
Manchester, Manchester, England, United Kingdom
We apply probabilistic characterization of grey matter diffusion complexity to patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD), and healthy controls of similar age. We find statistical differences in the regional median probabilities of observing n distinct dominant diffusion orientations between these subject groups providing evidence for the microstructural changes in grey matter associated with these pathologies. We find that the degree of abnormality in grey matter complexity increases in AD relative to MCI, consistent with the concept of MCI being a prodromal state of AD.