Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, United States of America.
Department of Psychology, Western University, London, ON, Canada.
PLoS One. 2023 Feb 8;18(2):e0262504. doi: 10.1371/journal.pone.0262504. eCollection 2023.
Verb and action knowledge deficits are reported in persons with Parkinson's disease (PD), even in the absence of dementia or mild cognitive impairment. However, the impact of these deficits on combinatorial semantic processing is less well understood. Following on previous verb and action knowledge findings, we tested the hypothesis that PD impairs the ability to integrate event-based thematic fit information during online sentence processing. Specifically, we anticipated persons with PD with age-typical cognitive abilities would perform more poorly than healthy controls during a visual world paradigm task requiring participants to predict a target object constrained by the thematic fit of the agent-verb combination. Twenty-four PD and 24 healthy age-matched participants completed comprehensive neuropsychological assessments. We recorded participants' eye movements as they heard predictive sentences (The fisherman rocks the boat) alongside target, agent-related, verb-related, and unrelated images. We tested effects of group (PD/control) on gaze using growth curve models. There were no significant differences between PD and control participants, suggesting that PD participants successfully and rapidly use combinatory thematic fit information to predict upcoming language. Baseline sentences with no predictive information (e.g., Look at the drum) confirmed that groups showed equivalent sentence processing and eye movement patterns. Additionally, we conducted an exploratory analysis contrasting PD and controls' performance on low-motion-content versus high-motion-content verbs. This analysis revealed fewer predictive fixations in high-motion sentences only for healthy older adults. PD participants may adapt to their disease by relying on spared, non-action-simulation-based language processing mechanisms, although this conclusion is speculative, as the analyses of high- vs. low-motion items was highly limited by the study design. These findings provide novel evidence that individuals with PD match healthy adults in their ability to use verb meaning to predict upcoming nouns despite previous findings of verb semantic impairment in PD across a variety of tasks.
帕金森病(PD)患者存在动词和动作知识缺陷,即使没有痴呆或轻度认知障碍也是如此。然而,这些缺陷对组合语义处理的影响还不太清楚。在先前的动词和动作知识发现的基础上,我们测试了以下假设:PD 会损害患者在在线句子处理过程中整合基于事件的主题适合信息的能力。具体来说,我们预计具有典型年龄认知能力的 PD 患者在视觉世界范式任务中的表现会比健康对照组差,该任务要求参与者根据主体-动词组合的主题适合性来预测受约束的目标对象。24 名 PD 患者和 24 名健康年龄匹配的参与者完成了全面的神经心理学评估。当他们听到预测性句子(渔夫摇晃小船)时,我们记录了参与者的眼球运动,旁边是目标、主体相关、动词相关和不相关的图像。我们使用增长曲线模型测试了组(PD/对照)对注视的影响。PD 和对照组参与者之间没有显着差异,这表明 PD 参与者成功且快速地使用组合主题适合信息来预测即将到来的语言。没有预测信息的基线句子(例如,看鼓)证实了两组表现出了等效的句子处理和眼球运动模式。此外,我们进行了一项探索性分析,对比了 PD 和对照组在低运动内容动词和高运动内容动词上的表现。该分析表明,只有健康的老年人在高运动句子中注视的次数更少。PD 患者可能通过依赖于未受损的、非动作模拟的语言处理机制来适应疾病,尽管这一结论是推测性的,因为高与低运动项目的分析受到研究设计的高度限制。这些发现提供了新的证据,表明 PD 患者能够像健康成年人一样,利用动词的含义来预测即将到来的名词,尽管之前在各种任务中发现 PD 患者存在动词语义损伤。