Cortical tau deposition follows patterns of entorhinal functional connectivity in aging
Abstract
Tau pathology first appears in the transentorhinal and anterolateral entorhinal cortex (alEC) in the aging brain. The transition to Alzheimer's disease (AD) is hypothesized to involve amyloid-b (Ab) facilitated tau spread through neural connections. We contrasted functional connectivity (FC) of alEC and posteromedial EC (pmEC), subregions of EC that differ in functional specialization and cortical connectivity, with the hypothesis that alEC-connected cortex would show greater tau deposition than pmEC-connected cortex. We used resting state fMRI to measure FC, and PET to measure tau and Aβ in cognitively normal older adults. Tau preferentially deposited in alEC-connected cortex compared to pmEC-connected or non-connected cortex, and stronger connectivity was associated with increased tau deposition. FC-tau relationships were present regardless of Aβ, though strengthened with Aβ. These results provide an explanation for the anatomic specificity of neocortical tau deposition in the aging brain and reveal relationships between normal aging and the evolution of AD.
Data availability
Data analyzed during this study are available as supporting files. Source data files have been provided for Table 1, Figure 2, Figure 2-figure supplement 1, Figure 3, Figure 3-figure supplement 1, and Supplementary File 2.
Article and author information
Author details
Funding
National Institutes of Health (R01-AG034570)
- William J Jagust
National Institutes of Health (F32-AG057107)
- Theresa M Harrison
Helmholtz Postdoc Program (PD-306)
- Anne Maass
Tau Consortium
- William J Jagust
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Inna Slutsky, Tel Aviv University, Israel
Ethics
Human subjects: All participants provided written informed consent. This study was approved by the Lawrence Berkeley National Laboratory institutional review board (protocol # 073H026).
Version history
- Received: June 7, 2019
- Accepted: August 31, 2019
- Accepted Manuscript published: September 2, 2019 (version 1)
- Version of Record published: September 27, 2019 (version 2)
Copyright
© 2019, Adams et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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