Ashish Raj1, Amy Kuceyeski, PhD1, Michael Weiner, MD2, Bruce Miller, MD3
1Department of Radiology, Weill Cornell Medical College, New York, NY, United States; 2Department of Radiology, University of California, San Francisco, San Francisco, CA, United States; 3Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
Recent studies on prion-like proteopathy of dementias suggest transmission along fiber pathways of the brain network. In a recent paper we modeled the macroscopic consequences of network-centric propagation as a diffusion process on the structural (tractography-derived) brain network. The model accurately recapitulated known patterns of atrophy seen in several dementias. To our knowledge network diffusion constitutes the first fully quantitative, testable model of macroscopic transmission of degenerative processes in the brain. Its neurologic impact arises from its implication that diverse proteopathic etiologies could produce shared spatial patterns whose explanation requires neither selective vulnerability nor focal points of origin, nor differential stressor loads. Here we highlight this new advance and put it in the wider context of graph theoretic modeling of dementias. We believe that researchers involved in neuroimaging of neurodegenerative diseases can benefit from a deeper understanding of this exciting new technology.