Matheu Gilson, Center for Brain and Cognition at Universitat Pompeu Fabra

Framework to extract and interpret biomarkers the spatio-temporal structure of fMRI data

Directed connectivity inference has become a cornerstone in neuroscience following the recent progress in neuroimaging techniques to characterize neuronal networks. In a recent study, we have developed a method to estimate cortical interactions from fMRI activity based on the multivariate Ornstein-Uhlenbeck process, yielding whole-brain effective connectivity, or EC [1]. This provides a fingerprint of the brain dynamics, which can be used in classification procedures to identify subjects' identities or the task they perform [2]. Based on a recent extension of the formalism in the direction of network theory [3], we can interpret the EC biomarkers for brain dynamics to perform community analysis. Compared to previous approaches, a strength of our approach is to take time into account, as EC characterizes the transition between fMRI activity across the network nodes. We obtain a quantitative picture of how fMRI activity flows in the network, initially segregated within communities, then becoming globally integrated (as described by a functional merging of the communities). The capabilities and limitations for the interpretation of our model-based approach in terms of brain communication will be then discussed [4].

References:
1) M Gilson, R Moreno-Bote, A Ponce-Alvarez, P Ritter, and G Deco. Estimation of directed effective connectivity from fmri functional connectivity hints at asymmetries of cortical connectome. PLoS Comput Biol, 12(3):e1004762, 2016.
2) V Pallares, A Insabato, A Sanjuan, S Kuehn, D Mantini, G Deco, M Gilson. Extracting orthogonal subject- and behavior-specific signatures from fMRI data using whole-brain effective connectivity. Biorxiv http://doi.org/10.1101/201624
3) M Gilson, N E Kouvaris, G Deco, and G Zamora-López. A novel framework to analyze complex network dynamics. arXiv, page 1712.05693, 2018.
4) Matthieu Gilson, Gustavo Deco, Karl Friston, Patric Hagmann, Dante Mantini, Viviana Betti, Gian Luca Romani, and Maurizio Corbetta. Effective connectivity inferred from fmri transition dynamics during movie viewing points to a balanced reconfiguration of cortical interactions. Neuroimage, Oct 2017.

Organized by

Henning Sprekeler, Laura Naumann & Loreen Hertäg

Location

TU Berlin, Room 4.063, Marchstraße 23, 10587 Berlin