Saved in:
Bibliographic Details
Main Authors: He, Tiantian, Jiang, Keyue, Zhao, An, Schroder, Anna, Thompson, Elinor, Soskic, Sonja, Barkhof, Frederik, Alexander, Daniel C.
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2508.07032
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918120974712832
author He, Tiantian
Jiang, Keyue
Zhao, An
Schroder, Anna
Thompson, Elinor
Soskic, Sonja
Barkhof, Frederik
Alexander, Daniel C.
author_facet He, Tiantian
Jiang, Keyue
Zhao, An
Schroder, Anna
Thompson, Elinor
Soskic, Sonja
Barkhof, Frederik
Alexander, Daniel C.
contents The long-term progression of neurodegenerative diseases is commonly conceptualized as a spatiotemporal diffusion process that consists of a graph diffusion process across the structural brain connectome and a localized reaction process within brain regions. However, modeling this progression remains challenging due to 1) the scarcity of longitudinal data obtained through irregular and infrequent subject visits and 2) the complex interplay of pathological mechanisms across brain regions and disease stages, where traditional models assume fixed mechanisms throughout disease progression. To address these limitations, we propose a novel stage-aware Mixture of Experts (MoE) framework that explicitly models how different contributing mechanisms dominate at different disease stages through time-dependent expert weighting.Data-wise, we utilize an iterative dual optimization method to properly estimate the temporal position of individual observations, constructing a co hort-level progression trajectory from irregular snapshots. Model-wise, we enhance the spatial component with an inhomogeneous graph neural diffusion model (IGND) that allows diffusivity to vary based on node states and time, providing more flexible representations of brain networks. We also introduce a localized neural reaction module to capture complex dynamics beyond standard processes.The resulting IGND-MoE model dynamically integrates these components across temporal states, offering a principled way to understand how stage-specific pathological mechanisms contribute to progression. The stage-wise weights yield novel clinical insights that align with literature, suggesting that graph-related processes are more influential at early stages, while other unknown physical processes become dominant later on.
format Preprint
id arxiv_https___arxiv_org_abs_2508_07032
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A Stage-Aware Mixture of Experts Framework for Neurodegenerative Disease Progression Modelling
He, Tiantian
Jiang, Keyue
Zhao, An
Schroder, Anna
Thompson, Elinor
Soskic, Sonja
Barkhof, Frederik
Alexander, Daniel C.
Machine Learning
Quantitative Methods
The long-term progression of neurodegenerative diseases is commonly conceptualized as a spatiotemporal diffusion process that consists of a graph diffusion process across the structural brain connectome and a localized reaction process within brain regions. However, modeling this progression remains challenging due to 1) the scarcity of longitudinal data obtained through irregular and infrequent subject visits and 2) the complex interplay of pathological mechanisms across brain regions and disease stages, where traditional models assume fixed mechanisms throughout disease progression. To address these limitations, we propose a novel stage-aware Mixture of Experts (MoE) framework that explicitly models how different contributing mechanisms dominate at different disease stages through time-dependent expert weighting.Data-wise, we utilize an iterative dual optimization method to properly estimate the temporal position of individual observations, constructing a co hort-level progression trajectory from irregular snapshots. Model-wise, we enhance the spatial component with an inhomogeneous graph neural diffusion model (IGND) that allows diffusivity to vary based on node states and time, providing more flexible representations of brain networks. We also introduce a localized neural reaction module to capture complex dynamics beyond standard processes.The resulting IGND-MoE model dynamically integrates these components across temporal states, offering a principled way to understand how stage-specific pathological mechanisms contribute to progression. The stage-wise weights yield novel clinical insights that align with literature, suggesting that graph-related processes are more influential at early stages, while other unknown physical processes become dominant later on.
title A Stage-Aware Mixture of Experts Framework for Neurodegenerative Disease Progression Modelling
topic Machine Learning
Quantitative Methods
url https://arxiv.org/abs/2508.07032