Evaluation of binaurally-synchronized dynamic-range compression algorithms for hearing aids

Binaural cues such as interaural level differences (ILD) are used, among other cues, to organize auditory perception and to segregate sound sources in complex acoustical environments. Dynamic-range compression working independently at each ear in a bilateral hearing aid, however, can alter these ILDs, potentially affecting sound source segregation. Binaural synchronization of compression algorithms might thus be necessary to preserve potentially beneficial spatial cues. This study presents a binaurally-linked model-based fast-acting dynamic compression algorithm designed to approximate the normal-hearing basilar membrane input-output function in hearing-impaired listeners. Aim of the evaluation was to assess the effect of binaural synchronization on speech intelligibility and listening effort in spatial masking conditions in comparison to bilateral fitting. Spatially symmetric and asymmetric masking conditions were used. A conventional multiband dynamic compression algorithm both implemented in a bilatera...