AUTHOR=Meyer-Baese Lisa , Anumba Nmachi , Bolt T. , Daley L. , LaGrow T. J. , Zhang Xiaodi , Xu Nan , Pan Wen-Ju , Schumacher E. H. , Keilholz Shella TITLE=Variation in the distribution of large-scale spatiotemporal patterns of activity across brain states JOURNAL=Frontiers in Systems Neuroscience VOLUME=18 YEAR=2024 URL=https://www.frontiersin.org/journals/systems-neuroscience/articles/10.3389/fnsys.2024.1425491 DOI=10.3389/fnsys.2024.1425491 ISSN=1662-5137 ABSTRACT=

A few large-scale spatiotemporal patterns of brain activity (quasiperiodic patterns or QPPs) account for most of the spatial structure observed in resting state functional magnetic resonance imaging (rs-fMRI). The QPPs capture well-known features such as the evolution of the global signal and the alternating dominance of the default mode and task positive networks. These widespread patterns of activity have plausible ties to neuromodulatory input that mediates changes in nonlocalized processes, including arousal and attention. To determine whether QPPs exhibit variations across brain conditions, the relative magnitude and distribution of the three strongest QPPs were examined in two scenarios. First, in data from the Human Connectome Project, the relative incidence and magnitude of the QPPs was examined over the course of the scan, under the hypothesis that increasing drowsiness would shift the expression of the QPPs over time. Second, using rs-fMRI in rats obtained with a novel approach that minimizes noise, the relative incidence and magnitude of the QPPs was examined under three different anesthetic conditions expected to create distinct types of brain activity. The results indicate that both the distribution of QPPs and their magnitude changes with brain state, evidence of the sensitivity of these large-scale patterns to widespread changes linked to alterations in brain conditions.