Effects of Aging on Speech-in-Noise Discrimination

The ability to discriminate speech in the presence of background noise decreases with age. The current study examined the effects of noise type and spatial separation between the target and masking speech on speech-in-noise (SiN) discrimination in older (22) and young (25) adults. Using Portable Automated Rapid Testing software implemented on an iPad, participants were asked to separate target speech from either interfering speech (informational masking) or 'garbled speech' that contained similar spectro-temporal aspects of sound, but no informational meaning (energetic masking) for three spatial separations (0°, 6°, and 45°). In addition, spectro-temporal modulation (STM) sensitivity, binaural sensitivity, and notched-noise masking thresholds were measured. Overall, older adults showed worse SiN performance compared to young controls for both types of masking at most of the spatial separations. In contrast to their worse sensitivity for binaural detection and notched-noise masking, older adults showed intact STM sensitivity. These findings add knowledge of how aging affects SiN discrimination and provide insight into training programs aimed at improving older adults' SiN performance.