Data-driven mapping between functional connectomes using optimal transport
This addresses the issue of improving interpretation and generalization for studies using different atlases in neuroscience, but it is incremental as it applies an existing mathematical technique to a known bottleneck.
The paper tackles the problem of mapping functional connectomes between different brain atlases without additional pre-processing, using optimal transport to transform time series and reconstruct connectomes, showing that transformed connectomes are significantly similar to gold-standard counterparts and maintain individual differences in brain-behavior associations.
Functional connectomes derived from functional magnetic resonance imaging have long been used to understand the functional organization of the brain. Nevertheless, a connectome is intrinsically linked to the atlas used to create it. In other words, a connectome generated from one atlas is different in scale and resolution compared to a connectome generated from another atlas. Being able to map connectomes and derived results between different atlases without additional pre-processing is a crucial step in improving interpretation and generalization between studies that use different atlases. Here, we use optimal transport, a powerful mathematical technique, to find an optimum mapping between two atlases. This mapping is then used to transform time series from one atlas to another in order to reconstruct a connectome. We validate our approach by comparing transformed connectomes against their "gold-standard" counterparts (i.e., connectomes generated directly from an atlas) and demonstrate the utility of transformed connectomes by applying these connectomes to predictive models based on a different atlas. We show that these transformed connectomes are significantly similar to their "gold-standard" counterparts and maintain individual differences in brain-behavior associations, demonstrating both the validity of our approach and its utility in downstream analyses. Overall, our approach is a promising avenue to increase the generalization of connectome-based results across different atlases.