Multi-scale analysis and computational modeling of intrinsic coupling modes in the ferret brain

点击翻译按钮获取中文摘要

Intrinsically generated dynamic coupling constitutes a key feature of brain activity. Available evidence suggests the existence of two types of intrinsic coupling modes (ICMs): Phase ICMs arise from phase coupling of oscillatory signals, whereas envelope ICMs result from coupled fluctuations of signal envelopes. Our overall goal is to systematically analyze and computationally model these types of ICMs in the ferret brain. Phase ICMs are widely studied neurophysiologically, but are not yet well understood in terms of modeling their relation to the structural connectome. Envelope ICMs have been extensively explored in connectomic models but are not well investigated with neurophysiological approaches. The interaction between these ICMs is almost completely unexplored and they have not yet been analyzed systematically in the same datasets. No computational modeling results have been reported for ICMs in the ferret brain. Using structural and functional connectomic datasets including large-scale electrocorticographic (ECoG-) recordings that we have previously acquired in the ferret, we will analyze both phase and envelope ICMs and provide a coherent computational modeling approach based on the structural connectome. The project will pursue the following key aims: (1) We will investigate phase ICMs by combining analysis of neurophysiological data and computational modeling; (2) we will analyze and model envelope ICMs; (3) we will investigate which interactions occur between phase and envelope ICMs. These aims map onto our work programme. Workpackage 1 will focus on the relation of phase ICMs to the structural connectome, on the spatiotemporal variability of phase coupling, on changes in phase ICMs associated with state changes, and on whether phase ICMs determine spreading waves and predict sensory stimulus processing. Workpackage 2 will study whether envelope ICMs differ in their relation to the structural connectome from phase ICMs, analyze the variability of envelope ICMs and their modulation by state changes, and test whether envelope ICMs in pre-stimulus activity predict sensory processing and form spreading waves. Workpackage 3 will investigate the relation between both types of ICMs and test whether they mutually predict each other in the context of state changes or network perturbation by stimuli. We will use the relation between signal phases and envelopes for quantifying large-scale connectivity, and investigate the relation of ICMs to dynamic phenomena such as criticality. We will provide an open-access repository of data and models used in this project (The Virtual Ferret) as part of TheVirtualBrain platform, which will facilitate data sharing and collaboration in the priority area of computational connectomics. The proposal addresses key themes of SPP 2041 by undertaking systematic analyses of complex network connectivity and developing computational models for explaining how network structure gives rise to neural dynamics.