Linking Local Dynamics to Network Organization in the Human Brain
Author | : Golia Shafiei |
Publisher | : |
Total Pages | : 0 |
Release | : 2022 |
ISBN-10 | : OCLC:1358412590 |
ISBN-13 | : |
Rating | : 4/5 (90 Downloads) |
Download or read book Linking Local Dynamics to Network Organization in the Human Brain written by Golia Shafiei and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The human brain is a complex network of anatomically connected and functionally interacting neuronal populations. Neural activity and functional interactions between brain areas are naturally variable from moment to moment, resulting in dynamic configurations of brain activity. Connectome architecture shapes the functional associations between brain areas, constraining both local and global brain dynamics. Contemporary theories of brain structure and function also emphasize systematic variations in cortical micro-architecture that are concomitant with macroscale variation in anatomical connectivity and functional interactions among neuronal populations. How the confluence of microscale gradients and macroscale network architecture manifests as dynamic neural activity remains unknown. This thesis explores the dynamical signature of haemodynamic and electromagnetic regional spontaneous neural activity and its association with cortical micro-architecture and large-scale network organization. Chapters 1 and 2 provide a brief introduction on spontaneous neural activity in the human brain and outline the main research questions presented throughout this thesis. Chapter 3 examines the interplay of local dynamics and global network interactions, using a single time-series property. Specifically, this chapter investigates how pharmacological manipulation of dopamine affects regional neural dynamics and how the observed changes in dynamics relate to global functional connectivity. The results demonstrate that disruption in normal levels of dopamine leads to increased haemodynamic signal variability and decreased functional connectivity, consistent with the stabilizing effects of dopamine on neural signaling. Chapter 4 takes an exploratory, data-driven approach to characterize the topographic organization of intrinsic dynamics across the cortex. Specifically, I derive a comprehensive, unbiased list of time-series features to quantify the dynamical fingerprint of spontaneous haemodynamic brain activity. The findings demonstrate a link between microscale gradients and macroscale connectivity, intrinsic dynamics, and cognition. Chapter 5 expands on the previous chapter and studies regional dynamics using neurophysiological activity with high temporal resolution instead of slower haemodynamic fluctuations. This chapter assesses the relationship between fast-oscillating neural activity and network embedding and determines the micro-architectural basis of neurophysiological activity. Chapter 6 seeks to jointly consider haemodynamic and neurophysiological activity by investigating the cross-modal correspondence between functional network architectures recovered from these two types of neural activity. The presented analyses indicate that the cross-modal coupling is regionally heterogeneous, reflecting cortical functional hierarchy and laminar differentiation. Finally, Chapter 7 provides an overview of the primary findings of this thesis and discusses their significance and implications for future research on human neural dynamics"--