Speaker: Julia Wang
PhD Candidate, Cold Spring Harbor Laboratory
Title: "Characterizing brain state heterogeneity with an interpretable manifold"
Abstract: Brain states are conventionally divided into wake, slow wave sleep (SWS) and rapid eye movement (REM) sleep based on distinct patterns of neural activity and muscle tone. These brain states are conventionally thought to be discrete, temporally sustained, and spatially global. Recent evidence indicates that this conventional definition of brain states may be insufficient, but such analyses have not been done systematically with large-scale neural recordings. Here we show this insufficiency using simultaneously recorded multi-day electromyogram (EMG) and local field potentials (LFP) across the cortex. We developed a computational approach to place these recordings on a low-dimensional manifold visualization. With this manifold, we characterized 9 substates of sleep and wake and their differences in expression and dynamics throughout the cortex. Particularly, we found a lack of REM-like activity in the lateral somatosensory cortex and an increase in theta rhythm in frontal cortex during wake. Our work provides a comprehensive quantification of deviations from canonical brain-state definition with a novel computational framework for analyzing brain states.