Abstract
This study aimed to characterize effects of bilateral bone conduction devices (BCD) including the Cochlear™ Osia(®) (Osia) and the Cochlear™ percutaneous Baha(®) Connect System (Baha) on localization of stationary and moving sound in children and adolescents with bilateral atresia. Participants were 11 listeners with BCDs [M(Age)(SD) = 14.7(3.5) years] and 11 age-matched controls [M(Age)(SD) = 14.9(1.9) years]. Outcomes were word recognition in quiet and noise, spatial release from masking (SRM) [spondee-word recognition thresholds in noise at co-located/0° or separated (90° left/right) positions], self-reported hearing using the Speech, Spatial and Qualities of Hearing Scale (SSQ), and localization of stationary and moving sound with tracking of real-time unrestricted head movements. BCD users had reduced speech perception accuracy in noise during unilateral listening (p < .001) and higher speech recognition thresholds than controls (p = .001). BCD users had higher errors than controls during stationary (p < .001) and moving (p < .001) sound localization consistent with self-reported spatial hearing challenges. BCD users had significantly reduced errors during bilateral use compared to unilateral use for stationary (p < .01) but not always for moving (right unilateral: p < .01; left unilateral: p = .46) sound localization. BCD users spent less time moving their heads in the correct direction compared to controls for stationary and moving sound localization (p < .01). Results indicate that children and adolescents with BCDs demonstrate improved localization of stationary but not moving sound-sources, with bilateral device use compared to unilateral use. This finding provides evidence for some access to binaural cues and mitigation of head shadow despite transcranial attenuation, but ineffective use of head movements.