In Vivo Tau, Amyloid, and Gray Matter Profiles in the Aging Brain

We provide a comparative in vivo examination of the brain network-based distribution of two hallmarks of Alzheimer's disease (AD) pathology in cognitively normal individuals: (1) Tau, detected with a novel positron emission tomography (PET) tracer known as F-18-AV-1451; and (2) amyloid-beta, quantified with C-11-PiB PET. We used a high-resolution graph-based approach to investigate local-to-local and local-to-distributed cortical associations between the maps of Tau, amyloid-beta, and gray matter intensity. Our study shows that Tau and amyloid-beta deposits are associated with distinctive spatial patterns of brain tissue loss. Moreover, Tau and amyloid-beta accumulations have strong network interdigitations in heteromodal and associative areas of the cortical mantle, particularly the inferior-lateral temporal lobe. These findings contribute significantly to our understanding of how these two main hallmarks of AD pathology propagate across the elderly human brain.