Complementary to mapping discrete regional boundaries, recent years have seen a rise of new methods and applications to study smooth spatial transitions — orgradients— in numerous aspects of brain organization. Already recognized in early post-mortem histological work, recent neuroimaging studies have mapped spatial gradients across morphology and microstructure, functional and structural connectivity, as well as task-based activation patterns. By recapitulating large-scale topographic principles of brain networks, the identification and analysis of cortical gradients may provide a framework to study brain organization across species, to examine changes in brain development and aging, and to more generally study the interrelation between brain structure, function and cognition.
The goal of this special issue is to interrogate methodological and neuroscientific questions, providing an overview of challenges and opportunities afforded by this emerging perspective. Topics of interest include:
- Novel methods for mapping spatial gradients in brain organization and to study variability across individuals in dimensional spaces
- Studies addressing the interplay between local transitions between areas and macroscale trends, and between gradients derived from different modalities
- Studies addressing macroscale gradients in animal models
- Empirical and theoretical work to study the role of large-scale gradients in neural circuit function and human cognition
- Critical analyses and reviews contextualizing gradient-based approaches with other methods in the field, including parcellation-based studies