Effect of lexical accessibility on syntactic production in aphasia: An eyetracking study.

purposeHealthy speakers use both word-level and structure-level information to ease sentence production processes. Structural priming facilitates message-structure mapping in aphasia. However, it remains unclear if and how word-level information affects off-line and on-line sentence production in persons with aphasia (PWA). This eyetracking-while-speaking study examined the effect of lexical priming on production of syntactic (active/passive) structures in PWA.

methodEleven PWA and twenty healthy older adults (HOA) described transitive actions (

resultsHOA showed increased production of passives over actives in the Theme vs. Agent prime condition. In eye fixation data, HOA showed priming-induced Theme advantage from the earliest time window (picture onset-400 milliseconds). PWA also showed a significant priming effect in off-line sentence production, with this priming effect being greater for the individuals whose syntactic processing is better preserved. In eye fixation data, however, PWA showed preferential fixations to the primed character at a later stage of sentence planning (400-800 milliseconds), following equal fixation time to Agent and Theme during the earliest time window.

conclusionHOA showed word-driven production in both off-line and real-time (eye fixations) production. Lexical accessibility effectively drove off-line syntactic production in PWA, especially for those whose syntactic capacity remains relatively preserved. However, PWA showed advanced processing of both characters in earliest eye fixation data, suggesting that successful word-driven off-line syntactic production was associated with atypical real-time sentence planning in aphasia.