Lexical co-occurrence and ambiguity resolution

Abstract

This study investigates the possible influence of lexical co-occurrence on lexical ambiguity resolution in sentence contexts. Lexical co-occurrence refers to similarity between the co-occurrence vectors of words, such that if two words have similar profiles of occurrence with other words, they are said to have a strong co-occurrence relationship. The present study examines whether lexical ambiguity resolution can be biased by the prior presentation of a word that shares a strong co-occurrence relationship with an ambiguous word under one of its meanings, despite the absence of plausibility support. Two “maze” word-by-word reading experiments examined highly implausible/anomalous sentences with balanced homographs. In sentences in which the ambiguous word (e.g., bat) was preceded by a biasing word with which it shares a strong co-occurrence relationship (e.g., umpire), (1) response times (RTs) to the ambiguous word were facilitated, and (2) garden-path effects were found when subsequent (disambiguating) information was incongruent with the biased meaning (e.g., The umpire tried to swallow the bat but its wings got stuck in his throat). Additional experiments showed that these biasing effects resist explanation in terms of a passive process of spreading activation. Furthermore, an eye-tracking experiment revealed a pattern of results comparable to that of the maze task experiments, indicating that these effects are not artefacts of the maze procedure. These results are taken to support a heuristic for lexical ambiguity resolution that is driven by relatively low-level intralexical connections based on lexical co-occurrence.