Age-Related Decline in Pragmatic Reasoning of Older Adults

Abstract As speech is often ambiguous, pragmatic reasoning—the process of integrating multiple sources of information including semantics, ostensive cues and contextual information (Bohn & Frank, 2019)—is essential to understanding a speaker’s intentions. Despite current literature suggesting that certain social cognitive processes such as gaze-processing (Slessor et al., 2014) appear to be impaired in late adulthood, it is not well understood if pragmatic reasoning decline with age. Here, we examined young adults’ (aged 19-25; n=41) and older adults’ (aged 60-79; n=41) ability to engage in pragmatic reasoning in a cue integration task. In Experiment 1, participants had to integrate contextual (participants and speaker knew there were two novel objects but the latter could only see one), semantic (“There’s the [novel-label]” or “Where’s the [novel-label]”), and gaze (speaker looked at the mutually-visible object) cues to identify the referent (Nurmsoo & Bloom, 2008). In Experiment 2, participants received contextual and semantic cues less gaze cue. In both experiments, the target referent object for “There” and “Where” trials was the mutually-visible object and the object the speaker could not see respectively. Overall, young adults outperformed older adults, even in the simpler two-cue Experiment 2 (ps<.006). While older adults were significantly above chance in “There” trials for both experiments as well as “Where” trials in Experiment 2 (ps<.05), they had specific difficulty in integrating three cues in “Where” trials, where a more sophisticated interpretation of the multiple cues was required (p=.42). Our findings provide important insights into an age-related decline of pragmatic reasoning in older adults.