Vogt, K., Frenzel, H., Ausili, S.A., Hollfelder, D., Wollenberg, B., Snik, A.F.M., and Agterberg, M.J.H.
Abstract Different amplification options are available for listeners with congenital unilateral conductive hearing loss (UCHL). For example, bone-conduction devices (BCDs) and middle ear implants. The present study investigated whether intervention with an active BCD, the Bonebridge, or a middle ear implant, the Vibrant Soundbridge (VSB), affected sound-localization performance of listeners with congenital UCHL. Listening with a Bonebridge or VSB might provide access to binaural cues. However, when fitted with the Bonebridge, but not with a VSB, binaural processing might be affected through cross stimulation of the contralateral normal hearing ear, and could interfere with processing of binaural cues. In the present study twenty-three listeners with congenital UCHL were included. To assess processing of binaural cues, we investigated localization abilities of broadband (BB, 0.5–20 kHz) filtered noise presented at varying sound levels. Sound localization abilities were analyzed separately for stimuli presented at the side of the normal-hearing ear, and for stimuli presented at the side of the hearing-impaired ear. Twenty-six normal hearing children and young adults were tested as control listeners. Sound localization abilities were measured under open-loop conditions by recording head-movement responses. We demonstrate improved sound localization abilities of children with congenital UCHL, when listening with a Bonebridge or VSB, predominantly for stimuli presented at the impaired (aided) side. Our results suggest that the improvement is not related to accurate processing of binaural cues. When listening with the Bonebridge, despite cross stimulation of the contralateral cochlea, localization performance was not deteriorated compared to listening with a VSB. Highlights • Improved sound localization abilities of children with congenital UCHL, when listening with a Bonebridge or VSB. • Improvement is not related to accurate processing of binaural cues. • Cross stimulation of the contralateral cochlea did not deteriorate localization performance. • Spectral cues can provide location information for horizontal sound localization. • Normal-hearing plugged listeners demonstrate deteriorated localization at the side of the open ear and of the plugged ear. [ABSTRACT FROM AUTHOR]