Effects of hearing and aging on sentence-level time-gated word recognition

Aging is known to influence temporal processing, but its relationship to speech perception has not been clearly defined. To examine listeners' use of contextual and phonetic information, the Revised Speech Perception in Noise test (R-SPIN) was used to develop a time-gated word (TGW) task.

In Experiment 1, R-SPIN sentence lists were matched on context, target-word length, and median word segment length necessary for target recognition. In Experiment 2, TGW recognition was assessed in quiet and in noise among adults of various ages with normal hearing to moderate hearing loss. Linear regression models of the minimum word duration necessary for correct identification and identification failure rates were developed. Age and hearing thresholds were modeled as continuous predictors with corrections for correlations among multiple measurements of the same participants.

While aging and hearing loss both had significant impacts on task performance in the most adverse listening condition (low context, in noise), for most conditions, performance was limited primarily by hearing loss.

Whereas hearing loss was strongly related to target-word recognition, the effect of aging was only weakly related to task performance. These results have implications for the design and evaluation of studies of hearing and aging.