Interregional brain interactions in children with unilateral hearing loss

Objective. To determine whether patterns of functional connectivity of cortical regions responsible for auditory processing and executive functions differ in children with unilateral hearing loss (UHL) versus their normal-hearing (NH) siblings. Study Design. Prospective observational study. Setting. Academic medical center. Subjects and Methods. Children with severe-to-profound UHL (9 right UHL, 7 left UHL) and 10 NH sibling controls were imaged using resting state functional connectivity magnetic resonance imaging (rs-fcMRI). All MRI images were transformed to a single common atlas; regions of interest (ROI) were chosen based on previous literature and unpublished results. Mean regionwise correlations and conjunction analyses were performed across 34 seed ROIs to identify temporally synchronized, low-frequency spontaneous fluctuations in the resting state blood oxygenation level-dependent signal that reveal functionally related regions. Results. Mean regionwise Student t tests found a left posterior opercular region with more correlated resting state activity with the inferior parietal lobule seed in the children with both left and right UHL than NH. In conjunction analysis, 4 regions showed different resting-state functional interactions between the NH and both UHL groups. These differences were in left medial globus pallidus, left middle temporal gyrus, right parahippocampal gyrus, and mid-cingulate cortex. These regions include areas associated with auditory processing, executive function, and memory formation. Conclusions. Resting state fcMRI identified differences in brain network interconnections between children with UHL and NH and may inform further investigation into the educational and behavioral difficulties experienced by children with UHL.