Bayesian Population Modeling of Effective Connectivity

Abstract. A hierarchical model based on the Multivariate Autoregessive (MAR) process is proposed to jointly model neurological time-series collected from multiple subjects, and to characterize the distribution of MAR coefficients across the population from which those subjects were drawn. Thus, inference about effective connectivity between brain regions may be generalized beyond those subjects studied. The posterior on population- and subject-level connectivity parameters are estimated in a Variational Bayesian (VB) framework, and structural model parameters are chosen by the corresponding evidence criteria. The significance of resulting connectivity statistics are evaluated by permutation-based approximations to the null distribution. The method is demonstrated on simulated data and on actual multi-subject neurological time-series.

• Type: Conference
• Year: 2005
• Where: IPMI
• Authors: Eric R. Cosman Jr., William M. Wells III
• Keywords: IPMI 2005, Medical Imaging, Multi-subject Neurological Time-series, Structural Model Parameters, Subject-level Connectivity Parameters