Popp Margot, Trumpp Natalie M, Kiefer Markus
Department of Psychiatry, Ulm University Ulm, Germany.
Front Hum Neurosci. 2016 Dec 15;10:637. doi: 10.3389/fnhum.2016.00637. eCollection 2016.
Grounded cognition theories suggest that conceptual representations essentially depend on modality-specific sensory and motor systems. Feature-specific brain activation across different feature types such as action or audition has been intensively investigated in nouns, while feature-specific conceptual category differences in verbs mainly focused on body part specific effects. The present work aimed at assessing whether feature-specific event-related potential (ERP) differences between action and sound concepts, as previously observed in nouns, can also be found within the word class of verbs. In Experiment 1, participants were visually presented with carefully matched sound and action verbs within a lexical decision task, which provides implicit access to word meaning and minimizes strategic access to semantic word features. Experiment 2 tested whether pre-activating the verb concept in a context phase, in which the verb is presented with a related context noun, modulates subsequent feature-specific action vs. sound verb processing within the lexical decision task. In Experiment 1, ERP analyses revealed a differential ERP polarity pattern for action and sound verbs at parietal and central electrodes similar to previous results in nouns. Pre-activation of the meaning of verbs in the preceding context phase in Experiment 2 resulted in a polarity-reversal of feature-specific ERP effects in the lexical decision task compared with Experiment 1. This parallels analogous earlier findings for primed action and sound related nouns. In line with grounded cognitions theories, our ERP study provides evidence for a differential processing of action and sound verbs similar to earlier observation for concrete nouns. Although the localizational value of ERPs must be viewed with caution, our results indicate that the meaning of verbs is linked to different neural circuits depending on conceptual feature relevance.
具身认知理论认为，概念表征本质上依赖于特定模态的感觉和运动系统。在名词中，已经对不同特征类型（如动作或听觉）的特定特征脑激活进行了深入研究，而动词中特定特征的概念类别差异主要集中在身体部位的特定效应上。本研究旨在评估动作和声音概念之间特定特征的事件相关电位（ERP）差异（如之前在名词中观察到的）是否也能在动词词类中发现。在实验1中，在词汇判断任务中向参与者视觉呈现精心匹配的声音和动作动词，该任务提供了对词义的隐性访问，并最大限度地减少了对语义词特征的策略性访问。实验2测试了在一个上下文阶段预先激活动词概念（其中动词与相关的上下文名词一起呈现）是否会调节词汇判断任务中后续特定特征的动作动词与声音动词的处理。在实验1中，ERP分析揭示了顶叶和中央电极处动作和声音动词的ERP极性模式不同，这与之前在名词中的结果相似。与实验1相比，实验2中在前一个上下文阶段对动词意义的预激活导致了词汇判断任务中特定特征的ERP效应的极性反转。这与之前关于启动的动作和声音相关名词的类似发现相似。与具身认知理论一致，我们的ERP研究为动作和声音动词的差异处理提供了证据，类似于早期对具体名词的观察。尽管必须谨慎看待ERP的定位价值，但我们的结果表明，动词的意义根据概念特征相关性与不同的神经回路相关联。
