Casey Paquola, PhD
Montreal Neurological Institute, McGill University
Título: How gradients of cortical architecture support large-scale functional dynamics
Resumen: I'll be discussing the functional significance of cytoarchitectural patterns across the cortex. This work builds upon a new approach to measure cortical architecture, which we developed on a volumetric reconstruction of a sliced and stained post mortem human brain then translated to microstructurally-sensitive MRI. In doing so, we identified a system-level gradient of microstructural differentiation traversing from primary sensory to limbic areas, which followed shifts in laminar differentiation and cytoarchitectural complexity. We found that large-scale gradients of microstructural differentiation overlapped with core axes of cortical dynamics but diverged towards transmodal cortical areas involved in more flexible aspects of cognition. By extending a surface-based model of the cortex to include the hippocampus (ie: allocortex), we could also show how specific features of cortical architecture and the intersection of the anterior-posterior processing streams underlie the hippocampus' putative role as a zone of convergence. Finally, using manifold learning techniques, we explored how multiple features of cortical wiring (spatial proximity, microstructural similarity and diffusion-based tractography) contribute to the functional organisation of the cortex. We found that the cortical wiring scheme sits upon intersecting cell-type specific gradients and supports multiple frequency-specific processing hierarchies, derived from intracranial EEG. All in all, we're working towards a multi-scale model of the cortex that can be used to interrogate the relationship between microstructure and function.