A novel brain partition highlights the modular skeleton shared by structure and function

Abstract

Elucidating the intricate relationship between brain structure and function, both in healthy and pathological conditions, is a key challenge for modern neuroscience. Recent progress in neuroimaging has helped advance our understanding of this important issue, with diffusion images providing information about structural connectivity (SC) and functional magnetic resonance imaging shedding light on resting state functional connectivity (rsFC). Here, we adopt a systems approach, relying on modular hierarchical clustering, to study together SC and rsFC datasets gathered independently from healthy human subjects. Our novel approach allows us to find a common skeleton shared by structure and function from which a new, optimal, brain partition can be extracted. We describe the emerging common structure-function modules (SFMs) in detail and compare them with commonly employed anatomical or functional parcellations. Our results underline the strong correspondence between brain structure and resting-state dynamics as well as the emerging coherent organization of the human brain.

What the structural-functional connectome reveals about brain aging: The key role of the fronto-striatal-thalamic circuit and the rejuvenating impact of physical activity

“…We used the BHA Brain Hierarchical Atlas (BHA, see 64 and Methods) with 2514 regions and calculated for each participant the weighted SC and FC connectivity matrices, representing respectively the region-pairwise streamline number and the region-pairwise Pearson correlation of resting-state activity time series.…”

“…It was also shown in 64 that the hierarchical brain partition with M = 20 modules was optimal based on the cross-modularity index X. This index was defined as the geometric mean between the modularity of the 10 All rights reserved.…”

“…The aforementioned 2514 brain regions were grouped into modules using the Brain Hierarchical Atlas (BHA), recently developed 64 and applied by the authors in a traumatic brain injury study 66 . The BHA is available to download at http://www.nitrc.org/projects/biocr_hcatlas/ .…”

“…Indeed, the key element is that the multi-scale modular BCA approach used in this work perfectly preserves the intrinsic link between structure and function. In fact, the resting activity is shaped by modular organization, where the structural and functional architecture clearly merge and match each other 64 . Therefore the multi-scale modular BCA approach used in this work perfectly preserves the intrinsic link between structure and function.…”

Temporal Excitation Patterns on the Cerebral Cortex as a Result of Migraine Modeling

“…The cortical geometry we used in this study has been reconstructed from a MRI scan with FreeSurfer image analysis suite (http://surfer.nmr.mgh.harvard.edu/ ): for further details, see [15] and references therein. This data set was already acquired and published in [16], and used in [1], and its acquisition was approved by the Ethics Committee at the Cruces University Hospital: all the methods employed were in accordance to approved guidelines. The data set corresponds to one healthy subject, male, age 28, and was acquired with a Philips Achieva 1.5T Nova scanner.…”