Abnormal functional connectivity and degree centrality in anterior cingulate cortex in patients with long-term sensorineural hearing loss

Wide-ranging functional remodeling is involved in sensorineural hearing loss (SNHL), which has been demonstrated to have accumulated risk of cognitive and emotional dysfunction. Anterior cingulate cortex (ACC) has close connections with the auditory area and plays a vital role in regulating the cognitive, emotional and auditory processing. However, the functional reorganization of the ACC and its associations with potential cognitive and emotional impairments involved in SNHL have never been explored. Thirty-five patients with long-term bilateral SNHL and thirty-five well-matched healthy controls were recruited for this study. We analyzed resting-state functional MRI data and neuropsychological test scores from these participants. Functional connectivity of the ACC subdivisions, voxel-wise degree centrality (DC) and intra-/internetwork connectivity were computed to evaluate the functional changes related to cognitive, emotional and multiple sensory functions. ANCOVA and post hoc analyses were conducted to identify differences between normal controls and patients for each measure. Widespread alterations of functional coupling with the subdivisions of the ACC were observed in regions involved in cognitive, emotional and multiple sensory processing, particularly within the cingulo-opercular network (CON), default mode network (DMN) and auditory network (AN) in the SNHL patients. Outstandingly increased DC was found in the ACC. Network analyses showed significant intra- and inter-network hypo-synchronization in the SNHL patients. Importantly, the functional alterations were associated with the anxiety states and the processing speed. The functional reorganization in the ACC and the disturbance of intrinsic multiple network functional connectivity among the CON, DMN, and AN were found in the SNHL patient, which might shed more lights on potential substrates underlying the cognitive and emotional impairments related to the SNHL.