Age-related temporal processing deficits: Relationship between temporal speech cue discrimination and gap detection abilities

Temporal processing abilities are crucial for encoding auditory information. These abilities decline with age, particularly impacting the ability to perceive brief temporal cues. Furthermore, age-related temporal processing deficits appear to be particularly detrimental for speech processing with degraded auditory input, such as that experienced by cochlear implant users. First, we hypothesized that reducing spectral information in speech would negatively impact temporal processing, with older listeners showing greater deficits. Twenty-two normal-hearing listeners, aged 20–70 years, completed temporal cue discrimination tasks involving silent interval duration using the stimuli dish versus ditch and gap detection tasks using vocoded speech. Results showed that the 50% crossover point for vocoded speech was about 5 ms later for older compared to younger listeners. Second, we hypothesized the individual variability in speech discrimination performance would correlate with gap detection thresholds. Results showed listeners with steeper word discrimination slopes also had better gap detection thresholds for the vocoded stimuli. These results emphasize the role of temporal processing in understanding speech with degraded spectral cues.