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Network Diffusion Modeling Explains Longitudinal Tau PET Data
Amelie Schäfer1, Elizabeth C Mormino2, Ellen Kuhl1
1Department of Mechanical Engineering, Stanford University, Stanford, CA, United States.
Frontiers in Neuroscience
|January 11, 2021
Summary
This study reveals how pathological tau spreads in the brain using network models and positron emission tomography. Findings help predict neurodegeneration timelines for Alzheimer's disease patients.
Area of Science:
- Neuroscience
- Biophysics
- Medical Imaging
Background:
- Alzheimer's disease involves tau protein accumulation, linked to neurodegeneration and cognitive decline.
- Current understanding of tau propagation relies heavily on postmortem studies, limiting insights into living brains.
Purpose of the Study:
- To investigate the propagation dynamics of misfolded tau in living humans.
- To test if tau spreads preferentially along neuronal connections.
Main Methods:
- Longitudinal positron emission tomography (PET) scans from 46 subjects over 3-4 years.
- Dynamic network modeling to simulate intracellular and extracellular tau spreading.
- Personalized model parameter identification for individual tau progression.
Main Results:
- Developed a network diffusion model to track pathological tau progression.
- Quantified protein production rates and intracellular diffusion coefficients.
- Demonstrated tau propagation along neuronal connections.
Conclusions:
- The network diffusion model offers a tool for early detection of non-clinical Alzheimer's symptoms.
- Enables personalized prediction of neurodegeneration timelines.
- Advances understanding of tauopathy progression in vivo.
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