Region-Referenced Spectral Power Dynamics of EEG Signals: A Hierarchical Modeling Approach

TL;DR

This paper introduces a hierarchical Bayesian modeling framework for analyzing region-referenced spectral power dynamics in EEG signals, enabling detailed insights into brain function during auditory learning, especially in autism spectrum disorder.

Contribution

It presents a novel hierarchical Bayesian approach using infinite factorial decompositions for multivariate EEG data, improving flexibility and efficiency in spectral power analysis.

Findings

Differential band power dynamics observed between TD and ASD children.

The model provides new insights into EEG spectral changes during auditory learning.

The approach enhances understanding of neural mechanisms in autism.

Abstract

Functional brain imaging through electroencephalography (EEG) relies upon the analysis and interpretation of high-dimensional, spatially organized time series. We propose to represent time-localized frequency domain characterizations of EEG data as region-referenced functional data. This representation is coupled with a hierarchical modeling approach to multivariate functional observations. Within this familiar setting, we discuss how several prior models relate to structural assumptions about multivariate covariance operators. An overarching modeling framework, based on infinite factorial decompositions, is finally proposed to balance flexibility and efficiency in estimation. The motivating application stems from a study of implicit auditory learning, in which typically developing (TD) children, and children with autism spectrum disorder (ASD) were exposed to a continuous speech stream. Using the proposed model, we examine differential band power dynamics as brain function is interrogated throughout the duration of a computer-controlled experiment. Our work offers a novel look at previous findings in psychiatry, and provides further insights into the understanding of ASD. Our approach to inference is fully Bayesian and implemented in a highly optimized Rcpp package.