Quintet Equipe

The proposed project aims at developing a methodology to identify significant transient brain states around a metastable ground state. How the brain seamlessly transitions, or "flows", from one state of network activity to another remains an open question in neuroscience. Neuroimaging studies have focused on mapping "static" representations of brain functional networks by averaging dynamical interactions between brain areas over long recording intervals, hence disregarding the importance of time. Drawing from the musical world, these static network representations are analogous to a harmony: a set of notes simultaneously played together, such as a piano chord, that produce a characteristic sound in unison. However it is not clear how the vast repertoire of the brain's possible notes and chords follow each other in a particular temporal sequence to yield the complex melody that underlies mental processes. To explore this important fundamental question, we will leverage on the recent evolution of whole-brain computational models capable of producing long time-series of simulated neural activity. We will then extend upon recent developments in graph signal processing, a technique mixing networks and dynamics, to ultimately characterize transient brain states from the simulated brain data.

Our project fits perfectly with research axes developed in Marseille and we have contacted two local teams whose expertise will be pivotal for the good development of our project: i) In the Centre de Physique Théorique (CPT), we will collaborate with Dr. Alain Barrat's group, whose expertise is in the statistical physics of complex systems and temporal networks. We will have access to computational facilities: two multi-core machines, hosted in the CPT. Upon assessment of the computational resources needed, we will apply for simulation time at the Mésocentre de Calcul (https://equipex-mesocentre.univ-amu.fr/). ii) At the Institut de Neurosciences de Systèmes (INS), we will collaborate with researchers from the Theoretical Neuroscience Group, in particular with Dr. Demian Battaglia, Dr. Simona Olmi and Dr. David Angulo-Garcia, whose expertise are in mathematical and computational models of brain networks. iii) Another collaborator of choice will be Dr. Alessandro Torcini, who is affiliated to the CPT, INS and the Institut de Neurobiologie de la Méditerranée (INMed) as Chaire d'Excellence A*Midex and whose research revolves, like our project, at the intersection of these institutions' themes. Our proposal will thus be beneficial to foster interactions among these laboratories, opening the way to collaborations which shall extend long after the end of the residency.