Brain-wide functional diffuse optical tomography of resting state networks

Area of Science:

• Neuroimaging
• Biomedical Engineering
• Computational Neuroscience

Background:

• Diffuse optical tomography (DOT) offers high spatio-temporal resolution for brain activity mapping.
• Previous DOT studies have reconstructed some resting state networks (RSNs), but not a comprehensive, brain-wide set comparable to functional MRI (fMRI).
• Reconstructing distributed RSNs with high fidelity remains a challenge for DOT.

Purpose of the Study:

• To develop and validate a novel brain-wide DOT (BW-DOT) framework for reconstructing comprehensive RSNs.
• To assess the capability of BW-DOT in mapping RSNs across the entire neocortical surface.
• To compare DOT-derived RSNs with established fMRI RSN templates and evaluate performance across different hemoglobin contrasts.

Main Methods:

• Development of a BW-DOT framework integrating a whole-head optode system.
• Application of computational techniques including finite-element modeling, inverse source reconstruction, and statistical correlation tomography.
• Reconstruction of RSNs using dual contrasts: oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (HbR).

Main Results:

• The BW-DOT framework successfully reconstructed a comprehensive set of RSNs and subnetworks covering the neocortical surface at both group and individual levels.
• DOT-derived RSNs exhibited statistically significant spatial similarities to fMRI RSN templates, including previously missed medial prefrontal cortex and precuneus networks.
• HbR RSNs showed greater similarity to fMRI templates, while HbO RSNs displayed more bilateral patterns; high robustness and reproducibility were demonstrated.

Conclusions:

• The developed BW-DOT framework is feasible for simultaneously mapping multiple RSNs with high fidelity.
• BW-DOT demonstrates potential as an accessible neuroimaging tool for studying RSNs, especially in patient populations.
• This technology advances the capability of DOT in brain network analysis, complementing fMRI.