Age-Related Changes in Temporal and Spectral Cue Weights in Speech

Listeners weight acoustic cues in speech according to their reliability, but few studies have examined how cue weights change across the lifespan. Previous work has suggested that older adults have deficits in auditory temporal discrimination, which could affect the reliability of temporal phonetic cues, such as voice onset time (VOT), and in turn, impact speech perception in real-world listening environments. We addressed this by examining younger and older adults' use of VOT and onset F0 (a secondary phonetic cue) for voicing judgments (e.g., /b/ vs. /p/), using both synthetic and naturally produced speech. We found age-related differences in listeners' use of the two voicing cues, such that older adults relied more heavily on onset F0 than younger adults, even though this cue is less reliable in American English. These results suggest that phonetic cue weights continue to change across the lifespan.