Abstract
Cortical connectivity conforms to a series of organizing principles that are common across species. Spatial proximity, similar cortical type, and similar connectional profile all constitute factors for determining the connectivity between cortical regions. We previously demonstrated another principle of connectivity that is closely related to the spatial layout of the cerebral cortex. Using functional connectivity from resting-state fMRI in the human cortex, we found that the further a region is located from primary cortex, the more distant are its functional connections with the other areas of the cortex. However, it remains unknown whether this relationship between cortical layout and connectivity extends to other primate species. Here, we investigated this relationship using both resting-state functional connectivity as well as gold-standard tract-tracing connectivity in the macaque monkey cortex. For both measures of connectivity, we found a gradient of connectivity distance extending between primary and frontoparietal regions. In the human cortex, the further a region is located from primary areas, the stronger its connections to distant portions of the cortex, with connectivity distance highest in frontal and parietal regions. The similarity between the human and macaque findings provides evidence for a phylogenetically conserved relationship between the spatial layout of cortical areas and connectivity.
Highlights
Cortical connectivity conforms to a series of organizing principles
Functional connectivity distance follows a gradient anchored in primary cortex We investigated the spatial distribution of connectivity distance based on resting-state functional connectivity in relation to locations of primary cortex
We found functional connectivity distance to systematically vary as a function of distance from primary cortex
Summary
Hilgetag 2006; Roberts et al 2016; Rubinov et al 2015; Vértes et al 2012), when they feature similar cortical microstructure (Barbas 2015; Beul et al 2015, 2017; Goulas et al 2016, 2017; Huntenburg et al 2017; Pandya et al 2015; Pandya and Sanides 1973; Pandya and Yeterian 1985), and when they share common connections to other cortical regions (Betzel et al 2016; Costa et al 2007; Song et al 2014; Vértes et al 2012) These principles are shared across a variety of species such as the mouse, cat, macaque, and. Connectivity distance peaked in regions of the default mode network (DMN)—regions that underwent disproportionate expansion during primate phylogeny (Hill et al 2010) and systematically occupy locations at maximal distance from primary cortex (Margulies et al 2016)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
