Individual Differences in the Expectation-based Comprehension of Korean Dative Sentences: An ERP Study

Abstract

Readers’ active use of linguistic cues from a given context elicits anticipatory processing of yet-to-be-encountered information. In this study, we aimed to examine whether the patterns of anticipatory comprehension would systematically differ by the degree of readers’ working memory capacity. Readers’ evoked responses potentials (ERPs) in response to words were recorded in the processing of Korean dative sentences (i.e., subject+[recipient+theme]/[theme-recipient]+adverb+verb) in which the presentation order of arguments (i.e., role predictability) and the likelihood corresponding to argument role fillers (i.e., word predictability) were manipulated. We found quantitative and qualitative differences in ERPs among readers during sentence comprehension. The N400 emerged in the integration of unpredictable words, and it occurred more frequently among readers with low working memory. Of our interest, we observed the asymmetrical distribution of the negativity and the positivity, attributable to the differences in readers’ working memory, at adverbs and verbs in which readers were busy with integrating previously-presented arguments into sentences and processing incoming words. Our results suggested that readers with low working memory are more involved in the lexical retrieval process, whereas those with high working memory are more attentive to the structural or semantic integration process. In short, we argued that the lack of working memory capacity could make readers fall behind in using lexical and structural information during sentence processing, particularly for argument integration.