Microstructural Superficial White Matter Covariance

This module samples superficial white matter intensities from a quantitative MRI in native qMRI space. This is achieved by constructing a series of equivolumetric surfaces between the gray matter boundary and 3 mm below it following a laplacian field. By parcellating and cross-correlating nodal intensity profiles, this module generates microstructural profile covariance (MPC) matrices describing similiarity in superficial white matter microstructure across the brain.

Superficial white matter surfaces are generated using scripts from the superficial-white-matter repository, available via GitHub by Jordan De Kraker.

-MPC_SWM

Prerequisites 🖐🏼

You need to run -proc_structural, -proc_surf and -post_structural before this stage

Processing stepsUsageOutputs

• Compute registration from qMRI to surface native space.

• Generate 16 equivolumetric surfaces between the gray matter boundary and 3 mm below it. Surfaces closest to gray matter boundary is then discarded to account for partial volume effects, resulting in 15 surfaces used for further analyses.

• Perform surface-based registration to fsaverage5, fsLR-32k, fsLR-5k templates

• Average intensity profiles within parcels defined on the native surface, while excluding outlier vertices

• Perform partial correlation, controlling for parcel-wide mean profile, across all pairs of intensity profiles