Prediction and Analysis of Connectivity in the Brain

Abstract

Neural brain connectivity has three aspects: a physical connection between different brain regions – termed anatomical connectivity; a mutual relationship between dynamical activities between different brain regions – termed functional connectivity; and the connectivity pattern that gives details of an influence one brain region has from other regions – termed effective connectivity. The anatomical and functional connectivities of the brain are experimentally measured in the form of connection matrices (CMs) by mapping the connectivity strengths between regions of interest (RoIs) of the brain using diffusion spectrum imaging (DSI) and functional magnetic resonance imaging (fMRI), respectively. However, the effective connectivity of the brain is difficult to measure experimentally. The thesis, firstly, infers direct and multistep effective connectivities from the functional connectivity of the brain and its relationship to cortical geometry in a healthy brain. Secondly, it presents a foundation to predict the impact on functional connectivity of the brain produced by lesions that are due to brain injuries. Finally, an analysis is presented of statistical properties of the connectivity strengths and its relation to brain connectivity mapping and cortical distances.