Insula-cingulate structural and functional connectivity: an ultra-high field MRI study

Author: Matthew A Cormie1,2, Batu Kaya1,2, Georgia E Hadjis1,2, Pedram Mouseli1,2, Massieh Moayedi1,2,3,4
1 Centre for Multimodal Sensorimotor and Pain Research, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
2 University of Toronto Centre for the Study of Pain, Toronto, ON, Canada.
3 Krembil Research Institute, University Health Network, Toronto, ON, Canada.
4 Department of Dentistry, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada.
Conference/Journal: Cereb Cortex
Date published: 2023 Jul 10
Other: Special Notes: doi: 10.1093/cercor/bhad244. , Word Count: 208

The insula and the cingulate are key brain regions with many heterogenous functions. Both regions are consistently shown to play integral roles in the processing of affective, cognitive, and interoceptive stimuli. The anterior insula (aINS) and the anterior mid-cingulate cortex (aMCC) are two key hubs of the salience network (SN). Beyond the aINS and aMCC, previous 3 Tesla (T) magnetic resonance imaging studies have suggested both structural connectivity (SC) and functional connectivity (FC) between other insular and cingulate subregions. Here, we investigate the SC and FC between insula and cingulate subregions using ultra-high field 7T diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI). DTI revealed strong SC between posterior INS (pINS) and posterior MCC (pMCC), and rs-fMRI revealed strong FC between the aINS and aMCC that was not supported by SC, indicating the likelihood of a mediating structure. Finally, the insular pole had the strongest SC to all cingulate subregions, with a slight preference for the pMCC, indicative of a potential relay node of the insula. Together these finding shed new light on the understanding of insula-cingulate functioning, both within the SN and other cortical processes, through a lens of its SC and FC.

Keywords: 7T; MRI; brain; diffusion; pain; salience network.

PMID: 37429832 DOI: 10.1093/cercor/bhad244