Mixed Effects Spectral Vector Autoregressive Model: With Application to Brain Connectivity

TL;DR

This paper introduces the ME-SpecVar model to analyze brain connectivity differences between healthy children and those with ADHD using EEG data, revealing significant connectivity patterns and variability in different frequency bands.

Contribution

The paper develops a novel mixed effects spectral VAR model for testing brain connectivity differences with subject-specific random effects in EEG frequency bands.

Findings

More significant connectivity in control group across all bands.

Children with ADHD show diminished connectivity and variability.

Diverse connectivity in parietal-occipital region linked to visual attention.

Abstract

The primary goal of this paper is to develop a method that quantifies how activity in one brain region can explain future activity in another region. Here, we propose the mixed effects spectral vector-autoregressive (ME-SpecVar) model to investigate differences in dynamics of dependence in a brain network between healthy children and those who are diagnosed with ADHD. Specifically, ME-SpecVar model will be used to formally test for significant connectivity structure obtained using filtered EEG signals in delta, theta, alpha, beta, and gamma frequency bands. The suggested model allows one-stage procedure for deriving Granger causality in common group structure and variation of subject specific random effects in different frequency oscillations. The model revealed novel results and showed more significant connections in all frequency bands and especially in slow waves in control group. In contrast, children with ADHD shared a pattern of diminished connectivity and variability of random effects. The results are consistent with previous findings about decreased anterior-posterior connectivity in children with ADHD. Moreover, the novel finding is that the most diverse subject specific effective connectivity parameters in healthy children belong to parietal-occipital region that is associated with conscious visual attention.