Department of Neurology and Penn Frontotemporal Degeneration Center, University of Pennsylvania, USA.
Department of Neurology and Penn Frontotemporal Degeneration Center, University of Pennsylvania, USA.
Cortex. 2018 Mar;100:127-139. doi: 10.1016/j.cortex.2017.08.030. Epub 2017 Sep 8.
Theories of grounded cognition propose that action verb knowledge relies in part on motor processing regions, including premotor cortex. Accordingly, impaired action verb knowledge in patients with amyotrophic lateral sclerosis (ALS) and Parkinson's Disease (PD) is thought to be due to motor system degeneration. Upper motor neuron disease in ALS degrades the motor cortex and related pyramidal motor system, while disease in PD is centered in the basal ganglia and can spread to frontostriatal areas that are important to language functioning. These anatomical distinctions in disease may yield subtle differences in the action verb impairment between patient groups. Here we compare verbs where the body is the agent of the action to verbs where the body is the theme. To examine the role of motor functioning in body verb production, we split patient groups into patients with high motor impairment (HMI) and those with low motor impairment (LMI), using disease-specific measures of motor impairment. Regression analyses assessed how verb production in ALS and PD was related to motor system atrophy. We find a dissociation between agent- and theme-body verbs in ALS: ALS HMI were impaired for agent body verbs but not theme verbs, compared to ALS LMI. This dissociation was not present in PD patients, who instead show depressed production for all body verbs. Although patients with cognitive impairment were excluded from this study, cognitive performance significantly correlated with the production of theme verbs in ALS and cognitive/stative verbs in PD. Finally, regression analyses related the agent-theme dissociation in ALS to grey matter atrophy of premotor cortex. These findings support the view that motor dysfunction and disease in premotor cortex contributes to the agent body verb deficit in ALS, and begin to identify some distinct characteristics of impairment for verbs in ALS and PD.
具身认知理论提出，动作动词知识部分依赖于运动加工区域，包括运动前皮质。因此，肌萎缩侧索硬化症（ALS）和帕金森病（PD）患者的动作动词知识受损被认为是由于运动系统退化。ALS 中的上运动神经元疾病会使运动皮质和相关的皮质脊髓运动系统退化，而 PD 中的疾病则集中在基底神经节，并可能扩散到对语言功能很重要的额纹状体区域。疾病中的这些解剖学差异可能会导致患者群体之间的动作动词损伤存在细微差异。在这里，我们比较了以身体为动作执行者的动词和以身体为主题的动词。为了研究运动功能在身体动词产生中的作用，我们根据运动障碍的特定测量值将患者分为运动障碍严重的患者（HMI）和运动障碍较轻的患者（LMI）。回归分析评估了 ALS 和 PD 中动词的产生与运动系统萎缩的关系。我们发现 ALS 中存在一种代理体和主题体动词的分离：与 ALS LMI 相比，ALS HMI 患者在代理体动词上受损，但在主题体动词上没有受损。这种分离在 PD 患者中并不存在，相反，所有的身体动词的产生都受到抑制。尽管这项研究排除了有认知障碍的患者，但认知表现与 ALS 中主题动词和 PD 中认知/静态动词的产生显著相关。最后，回归分析将 ALS 中的代理-主题分离与运动前皮质的灰质萎缩联系起来。这些发现支持了运动功能障碍和运动前皮质疾病导致 ALS 中代理体动词缺陷的观点，并开始确定 ALS 和 PD 中动词损伤的一些独特特征。
