A heuristic branch-and-bound based thresholding algorithm for unveiling cognitive activity from EEG data

Abstract

One of the biggest challenges in the field of computational neuroscience from the perspective of complex network analysis is the measurement of dynamic local and global interactions of the brain regions during cognitive function. Graph theoretic analysis has been extensively applied to study the dynamics of functional brain networks in the recent years. The selection of appropriate thresholding methods to construct weighted/unweighted subnetworks to detect cognitive load induced changes in brain׳s electrical activity remains an open challenge in the functional brain network research. This paper reviews the application of statistical and information theoretic metrics to construct the functional brain networks, proposes a novel Branch-and-Bound based thresholding algorithm that extracts the influential subnetwork, and applies efficient computational techniques and complex network metrics to detect and quantify the cognitive activities. The empirical analyses showcase the efficiency of the proposed thresholding algorithm by highlighting the changing neuronal patterns during cognitive activity when compared to that of baseline activity. Statistical evaluation of the results further validates the efficiency of the proposed method as well. The results demonstrate the ability of the proposed algorithm in detecting subtle cognitive load induced changes in functional brain networks.