Cabral, JoanaFernandes, Henrique M.Van Hartevelt, Tim J.James, Anthony C.Kringelbach, Morten L.Deco, Gustavo2015-01-272015-01-272013Cabral J, Fernandes HM, Van Hartevelt TJ, James AC, Kringelbach, ML, Deco G. Structural connectivity in schizophrenia and its impact on the dynamics of spontaneous functional networks. Chaos. 2013 Dec 23;23(4):046111. DOI 10.1063/1.48511171054-1500http://hdl.handle.net/10230/23076The neuropathology of schizophrenia remains unclear. Some insight has come from modern/nneuroimaging techniques, which offer an unparalleled opportunity to explore/nin vivo/nthe structure/nand function of the brain. Using functional magnetic resonance imaging, it has been found that the/nlarge-scale resting-state functional connectivity (rsFC) in schizophrenia — measured as the/ntemporal correlations of the blood-oxygen-level-dependent (BOLD) signal — exhibit altered/nnetwork topology, with lower small-world index. The origin of these rsFC alterations and link with/nthe underlying structural connectivity remain unclear. In this work, we used a computational model/nof spontaneous large-scale brain activity to explore the role of the structural connectivity in the/nlarge-scale dynamics of the brain in health and schizophrenia. The structural connectomes from 15/nadolescent patients with early-onset schizophrenia and 15 age- and gender-matched controls were/nbuilt from diffusion tensor imaging data to detect the white matter tracts between 90 brain areas./nBrain areas, simulated using a reduced dynamic mean-field model, receive excitatory input from/nother areas in proportion to the number of fibre tracts between them. The simulated mean field/nactivity was transformed into BOLD signal, and the properties of the simulated functional networks/nwere analyzed. Our results suggest that the functional alterations observed in schizophrenia are not/ndirectly linked to alterations in the structural topology. Instead, subtly randomized and less/nsmall-world functional networks appear when the brain operates with lower global coupling, which/nshifts the dynamics from the optimal healthy regime.10 p.application/pdfeng© American Institute of Physics. This article appeared in Cabral J et al., Chaos, Vol. 23(4), 2013 and may be found at http://dx.doi.org/10.1063/1.4851117info:eu-repo/semantics/articlehttp://dx.doi.org/10.1063/1.4851117info:eu-repo/semantics/openAccess