arXiv Machine Learning

Uncertainty calibration in Bayesian M/EEG source imaging

arXiv Machine Learning
Oct 23

Spectral Uncertainty Decomposition for Sparse Bayesian Learning

The paper introduces a spectral framework that decomposes the posterior covariance in sparse Bayesian learning for M/EEG source imaging into data‑informed and indeterminacy epistemic components, using the singular value structure of the prior‑preconditioned forward operator. It also presents an equivalent subtractive decomposition that expresses the prior covariance as the sum of posterior and data‑driven reduction terms, allowing precise accounting of uncertainty reduction through Bayesian learning. These complementary representations provide both theoretical insight and practical tools for interpretable uncertainty quantification in linear‑Gaussian Bayesian inverse solvers where the posterior covariance is available in closed form.

By Ismail Huseynov, Stefan Haufe
arXiv Statistics ML
Sep 28

Bayesian Uncertainty Quantification for fMRI Functional Connectivity via Simulation-Based Inference

The paper introduces a Bayesian framework that models BOLD dynamics as coupled Ornstein‑Uhlenbeck processes and uses Sequential Neural Posterior Estimation to produce connectivity posteriors while accounting for measurement noise. Applied to 28 healthy controls scanned at 7T, the method quantifies uncertainty from scanner noise, subject variability, and scan length, revealing that about 46 voxels per ROI and 7 minutes of 7T data suffice for 90% of asymptotic precision. It also shows that 7T achieves within‑session precision 40% faster than 3T and requires roughly 37 times less per‑subject scan time to reach population‑level convergence, offering concrete, scanner‑specific guidance for protocol optimization.

By Simon Carter, Zeming Kuang, Lilianne R. Mujica-Parodi, Helmut H. Strey