The ability to make sense of sound relies, in some measure, on the fidelity with which the temporal information within that sound is encoded in the auditory system and interpreted by the brain. One facet of hearing where temporal processing plays an important role is spatial hearing. Good binaural hearing confers advantages such as spatial release from masking, which is the benefit to masked speech intelligibility of separating the target and masker speech sources in space. Older listeners – even those with ‘near-normal’ hearing – tend to have compromised binaural temporal processing and exhibit less binaural advantage. Determining the factors that underlie this is key to understanding the constraints on the abilities of older listeners to communicate and function in the spatially and acoustically complex soundscape of our every-day environment. The purpose of this project is to obtain a comprehensive characterization of the spatial hearing abilities of adults across a wide age range, with a particular emphasis on differentiating effects of age and hearing loss. This will have particular relevance to understanding the hearing difficulties of older listeners with otherwise ‘near-normal’ hearing. Specific Aims focus on binaural temporal processing and spatialized speech-in-speech recognition, particularly under dynamic conditions. The approach uniquely combines behavioral and electrophysiological measures, and also incorporates the listener’s cognitive profile. The findings will advance our understanding of the benefits of spatial hearing, and the dependence of these benefits on the fidelity of temporal information available to the listener. These outcomes will be directly relevant to the public health challenge of addressing the communication difficulties experienced by the burgeoning older population.

The relevance of this project to public health is that it advances our understanding of the hearing difficulties experienced by older listeners, both with and without hearing loss, in everyday settings where multiple sound sources are present at the same time. Social wellbeing relies on the ability to communicate in this complex soundscape so it is essential to understand the spatial hearing skills necessary to function successfully in these environments. The findings of this project will be directly relevant to the public health challenge of addressing the communication difficulties experienced by the burgeoning older population.