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bioRxiv · 10.64898/2026.10.02.756182

MICROSTRUCTURAL ORGANIZATION OF CORTICO-SUBCORTICAL FUNCTIONAL CONVERGENCE

Verma, P.·Singh, S.·Dang, S.
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Abstract

The human subcortex integrates information from distributed cortical regions through functionally organized cortico-subcortical systems. Using the publicly available MICA-MICs multimodal MRI dataset of 50 healthy adults, we characterized the microstructural organization of functionally converging cortical regions. First, using resting-state fMRI., we identified cortical regions converging on subcortical targets, including thalamic, basal ganglia, and subcortical limbic structures. Then, using depth-resolved quantitative T1 profiles, we constructed a convergence-restricted microstructural profile covariance matrix, followed by diffusion-map embedding. The first microstructural gradient predominantly differentiated primary and association cortex, whereas the second gradient showed target-related differentiation beyond differences in primary versus association cortex. Cytoarchitectural analysis further revealed target-related differences in cortical composition. Together, these findings reveal complementary dimensions of cortico-subcortical functional organization, spanning broad cortical hierarchy, target-related microstructural differentiation, and cytoarchitectural composition.

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Verma, P., Singh, S., Dang, S.. 2026-10-08. MICROSTRUCTURAL ORGANIZATION OF CORTICO-SUBCORTICAL FUNCTIONAL CONVERGENCE. https://doi.org/10.64898/2026.10.02.756182

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