Functional and structural brain connectivity in congenital deafness

Abstract

Several studies have been carried out to verify neural plasticity and the language process in deaf individuals. However, further investigations regarding the intrinsic brain organization on functional and structural neural networks derived from congenital deafness is still an open question. The objective of this study was to investigate the main differences in brain organization manifested in deaf individuals, concerning the resting-state functional patterns, and white matter structuring. Functional and diffusion-tensor magnetic resonance imaging modalities were acquired from 18 congenitally deaf individuals and 18 age-sex-matched hearing controls. Compared to the hearing group, the deaf individuals presented higher functional connectivity (FC) among the posterior cingulate cortex node of the default mode network (DMN) with visual and motor networks, lower FC between salience networks, language networks, and prominence of functional connectivity changes in the right hemisphere, mostly in the frontoparietal and temporal lobes. In terms of structural connectivity (SC), we found changes mainly in the occipital and parietal lobes, involving both classical sign language support regions as well as concentrated networks for focus activity, attention, and cognitive filtering. Our findings elucidate the general brain network modifications, contributing to a better understanding of brain plasticity driven by deafness.

Crossmodal reorganization in deaf auditory cortices compensates for the impaired body-centered visuomotor transformation after early deafness

“…Efficient task performance was associated with stronger modularity in the task-negative DMN in terms of higher within-module connectivity in the DMN and lower between-module connectivity between the DMN and the task-relevant neural networks (Gonzalez-Castillo and Bandettini, 2017). It has been suggested that the DAN and the FPN, two task-critical networks supporting the egocentric task, show stronger functional and structural connectivity with the DMN in early deaf people (Dell Ducas et al, 2021;Li et al, 2022). Moreover, the increased inter-network connectivity between the task-irrelevant DMN and the task-relevant DAN and FPN was associated with impaired egocentric performance in congenitally deaf people (Li et al, 2022).…”