Network analysis of infant brain functional connectivity using spectral EEG

Abstract

Currently MRI is the primary method used to calculate brain connectivity in sleeping infants. In this study, we analysed functional connectivity in infants through event-related potentials (ERP) calculated using electroencephalogram (EEG). Time locked EEG is cheaper than MRI and provides temporally precise brain response. Each electrode of the EEG acquisition cap used for recording the EEG signals served as a node in the derived connectivity network. Finally, we have calculated connectivity network measures like characteristic path length (CPL), global efficiency (GE), and average clustering coefficient (ACC) for each infant. Both term and pre-term infant's resting state connectivity was characterised by a dense cluster between central and centro-parietal locations. However, the tactile network in term infants displayed lateralisation to the centro-parietal locations overlaying the somatosensory cortex, while the pre-term's tactile network was dense between frontal and central locations. Overall, the tactile network CPL decreased, while GE and ACC increased with higher gestational age at birth, indicating increased efficiency. This is the first study demonstrating differences between tactile functional connectivity in term and pre-term infants using EEG. We suggest that network measures like CPL, GE and ACC may be used as biomarkers of tactile-dependent functional outcomes in early childhood.