The effects of semantic predictability in non-pathological older adults' production of a phonemic contrast

The present study examined the effects of semantic predictability in non-pathological older adults' production of the /t/-/d/ phonemic voice contrast. Experiment 1 examined young and older adults' production of /t/ and /d/ words embedded in semantically biasing and neutral passages and when produced in the clear or in noise. Experiment 2 assessed the perceptual intelligibility of subjects' production by examining listeners' identification of the /t/-/d/ words produced in Experiment 1. The results replicate previous findings demonstrating that duration lengthens in neutral vs. biasing contexts. However, the results also show agerelated differences. Older adults preserved the /t/-/d/ contrast in all the experimental manipulations; young adults were more variable. In addition, listeners were better able to identify the words produced by the older adults. We suggest that older adults compensate pragmatically for their cognitive inability to integrate and process the semantic information in the neutral context...