Cytoarchitecture and brain-wide connectivity reveal topographic organization of insula networks

COEX 

One of the major challenges to carrying out in vivo neuroanatomical analyses is that regional cytoarchitectural variation is difficult to capture by MRI. As a result, parcellation of brain regions is often limited to a scale too coarse for the understanding of their functions. While this presents a challenge for many regions of the brain, the insula is comprised of distinct laminar cyto-archetypes that form the basis of highly integrative whole brain networks. These subregions have been linked to an astonishing number of functional roles, and may ultimately be targets for future development of interventions in physical and mental health ^1–4. In order to capture the heterogeneity of these subregions and networks, it is necessary to improve the specificity of neuroanatomical data and analyses using resolutions across disparate spatial scales and contrasting modalities from within the same subjects. We present our first integrated (Mic)ro to (Mac)ro Macaque brain dataset, here called MicMac (Fig. 1). MicMac is an extendable workflow, represented by a within-subject whole brain dataset that integrates aligned multi-parametric in vivo MRI, high resolution ex vivo MRI, and histology within a single, standardized template space. We then translate this workflow to perform a group level network analysis to identify network features in an in vivo cohort of n=16 middle to older aged macaques (7-20 years, 3M, 13F).