Selective Word Stress Effect for Speech Perception Enhancement in Hearing-Impaired Older Listeners

Purpose: Although it is known that communication problem of the older adults might be overcome by using slower speech or talking in a less noisy environment, there is still a lack of detailed skills. This study aimed to identify word stress benefit in speech perception for older listeners when different levels of background noise and speech rate were presented. Methods: Forty elderly (20 for hearing loss and 20 for normal hearing) were randomly recruited. Both groups conducted sentence tests at quiet and three signal-to-noise ratio (SNR) (+6, +3, 0 dB) and did them under four timealteration conditions (± 30% and ± 15%). Further, all sentences of both the noise and time alteration conditions had a 4, 6, or 8 dB up emphasized key word. Results: As expected, the hearing-impaired group had lower scores than the group with normal hearing in quiet and three SNR conditions. In quiet, both groups performed best at 6 dB emphasis. However, there was no significant difference in performance across 4, 6, and 8 dB up stress conditions when background noise was present. As time compression increased, speech perception scores decreased in both groups. Notably, at 30% expansion (slower speed), the normal hearing group scored the highest at 4 dB up emphasis, while the hearing-impaired group showed the best performance best at 8 dB up emphasis. Conclusion: Based on the current results, rather than simply speaking slowly, it would be more helpful for older adults with hearing loss to control their speech rate also emphasize key words during the conversation.