16 research outputs found
Spectral Characterization of functional MRI data on voxel-resolution cortical graphs
The human cortical layer exhibits a convoluted morphology that is unique to
each individual. Conventional volumetric fMRI processing schemes take for
granted the rich information provided by the underlying anatomy. We present a
method to study fMRI data on subject-specific cerebral hemisphere cortex (CHC)
graphs, which encode the cortical morphology at the resolution of voxels in
3-D. We study graph spectral energy metrics associated to fMRI data of 100
subjects from the Human Connectome Project database, across seven tasks.
Experimental results signify the strength of CHC graphs' Laplacian eigenvector
bases in capturing subtle spatial patterns specific to different functional
loads as well as experimental conditions within each task.Comment: Fixed two typos in the equations; (1) definition of L in section 2.1,
paragraph 1. (2) signal de-meaning and normalization in section 2.4,
paragraph
Graph Spectral Characterization of Brain Cortical Morphology
The human brain cortical layer has a convoluted morphology that is unique to
each individual. Characterization of the cortical morphology is necessary in
longitudinal studies of structural brain change, as well as in discriminating
individuals in health and disease. A method for encoding the cortical
morphology in the form of a graph is presented. The design of graphs that
encode the global cerebral hemisphere cortices as well as localized cortical
regions is proposed. Spectral metrics derived from these graphs are then
studied and proposed as descriptors of cortical morphology. As proof-of-concept
of their applicability in characterizing cortical morphology, the metrics are
studied in the context of hemispheric asymmetry as well as gender dependent
discrimination of cortical morphology.Comment: arXiv admin note: substantial text overlap with arXiv:1810.1033