Lexical Ambiguity Resolution Using Discourse Contexts in Persons With and Without Aphasia.

Abstract

The purpose of this study was to investigate the ability of persons with aphasia (PWA) to resolve different types of ambiguous words (homophones, metaphors, and metonyms) in discourse contexts. Six PWA and 10 controls listened to short discourses that biased either the dominant (more frequent) or subordinate (less frequent) version of an ambiguous word as well as nonsense (filler) discourses. Participants then indicated whether or not the final sentence, which contained the ambiguity, made sense in the discourse. Data for both accuracy and reaction time were collected. There was no significant Group × Word Type × Frequency interaction in the reaction time data. In the accuracy analysis, there was a significant Group × Frequency × Word Type interaction, which appeared to be driven by the PWA's relative accuracy with subordinate homophones and relative inaccuracy with subordinate metaphors. These results suggest that PWA were able to use discourse contexts to resolve subordinate versions of literal ambiguous words but have difficulty resolving metaphoric ambiguous words. Further investigations should be done to clarify how much context PWA require to successfully resolve lexical ambiguities.