Flowchart exemplifying the building of the connectivity matrixes in the brain for MRI structural data.
(1) A T1 or T2-weighted MRI image is preprocessed to account for some artifacts and a meaningful variable is extracted for each brain region defined by the chosen parcellation scheme (e.g. cortical thickness, subcortical volume).
(2) Correlation coefficients are calculated for each pair of brain regions in the brain across the subjects of a group.
(3) The connectivity matrix is built such that the rows and the columns represent the brain regions and the entries are the correlation coefficients between each pair of brain regions.