Functional connectivity modelling in fMRI based on causal networks

F.F. Deleus1, P.A. De Maziere1, M.M. Van Hulle1
1Laboratorium voor Neurn en Psychofysiologie, Katholieke Universiteit Leuven, Leuven, Belgium

Tóm tắt

We apply the principle of causal networks to develop a new tool for connectivity analysis in functional magnetic resonance imaging (fMRI). The connections between active brain regions are modelled as causal relationships in a causal network. The causal networks are based on the notion of d-separation in a graph-theoretic context or, equivalently, on the notion of conditional independence in a statistical context. Since relationships between brain regions are believed to be nonlinear in nature, we express the conditional dependencies between the brain regions' activities in terms of conditional mutual information. The density estimates needed for computing the conditional mutual information are obtained with topographic maps, trained with the kernel-based maximum entropy rule (kMER).

Từ khóa

#Intelligent networks #Brain modeling #Numerical analysis #Mutual information #Equations #Entropy #Neuroimaging #Testing #Laboratories #Psychology

Tài liệu tham khảo

pearl, 1997, Graphs Causality and Structural Equation Models 10.1162/089976698300017179 van hulle, 2000, Faithful Representations and topographic maps From distorlion-to information-based self-organization peuskens, 2001, Human brain regions involved in heading estimation, J Neuroscience, 21, 2451, 10.1523/JNEUROSCI.21-07-02451.2001 spirtes, 1990, Causality from Prob-ability, Evolving Knowledge in Natural Science and Artificial Intelligence, 181 spirtes, 1993, Causation, Prediction, - and Search, 10.1007/978-1-4612-2748-9 10.1016/B978-1-4832-8287-9.50049-9 greenstein, 1999, Color atlas of neuroscience, 10.1055/b-005-148864 spirtes, 1995, Directed Cyclic Graphical Representation of Feedback Models, Proc 11th Conf Uncertainty in Artificial Intelligence richardson, 1999, Automated discovery of linear feedback models, Computation Causation and Discovery, 253 10.1093/cercor/7.8.768 10.1002/hbm.460020104 10.1002/(SICI)1097-0193(1998)6:5/6<403::AID-HBM14>3.0.CO;2-9 10.1214/aoms/1177732676 jordan, 2001, Graphical Models: Foun-dations-of Neural Computation 10.1098/rstb.1999.0477 10.1002/hbm.460010108 10.1073/pnas.97.13.7591 pearl, 1988, Probabilistic Reasoning in Intelligent Systems