The Default Mode Network and Visual Network Functional Connectivity Changes in Noise-Induced Hearing Loss Patients: A Resting-State fMRI Study

Abstract

Background: Hearing loss affects communication and hinders personal attention and cognitive ability. We hypothesized that noise-induced hearing loss (NIHL) patients during long-term noise exposure may result in multimodal plastic changes in the nonauditory central nervous system.

Objective: To investigate the functional connectivity (FC) of the default mode network (DMN) and visual network (VN) in patients with occupational NIHL using resting-state functional magnetic resonance imaging (rs-fMRI).

Methods: Ninety-eight people with NIHL and 78 healthy controls (HCs) matched for age and educational level were enrolled. The mini-mental state examination (MMSE) was conducted, and rs-fMRI scanning was performed. The data were processed and analyzed to identify FC changes between DMN, VN, and the whole brain.

Results: Compared with the HCs, the NIHL group showed significantly enhanced connectivity with multiple brain regions when utilizing the DMN as seed regions of interest (ROI), with only some brain regions showing significantly decreased connectivity. When the VN was used as the seed ROI, the NIHL group showed significantly enhanced connectivity with multiple brain regions (corrected by GRF, p < 0.05). In the present study, the FC between multiple brain areas of VN and DMN in the NIHL patient group was enhanced compared to the normal population. The phenomenon of "perceptual compensation" is confirmed. The results of this study suggest that NIHL causes various changes in brain function related to emotion, decision-making, social cognition, and psychopathology. It suggests that changes in brain functional networks involve complex processes involving plasticity and damage to multiple networks.

Conclusions: The NIHL patients showed abnormal FC changes in both the DMN and VN, indicating widespread multimodal plasticity and reorganization of nonauditory central nervous system functions in people with NIHL.

Keywords: default mode network (DMN); functional connectivity (FC); functional magnetic resonance imaging (fMRI); noise‐induced hearing loss (NIHL); visual network (VN).