Department of Psychology, University of Milano-Bicocca, Viale dell'Innovazione 11, 20125, Milan, Italy.
Behav Brain Funct. 2009 Jul 29;5:33. doi: 10.1186/1744-9081-5-33.
Electrophysiological, hemodynamic and neuropsychological studies have provided evidence of dissociation in the way words belonging to different semantic categories (e.g., animals, tools, actions) are represented in the brain. The aim of the present study was to investigate whether a word's semantic domain may affect the amplitude and latency of ERP components, independently of any other factor.
EEGs were recorded from 16 volunteers engaged in a lexical decision task (word/non-word discrimination) involving 100 words (flora and fauna names). This task allowed us to evaluate differences in processing between words belonging to different categories (fauna vs. flora) independently of task demands. All stimuli were balanced in terms of length, frequency of occurrence, familiarity and imageability. Low Resolution Electromagnetic Tomography (LORETA) was performed on ERP difference waves of interest.
Our findings showed that the two categories were discriminated as early as 200 ms post-stimulus, with larger responses to flora names over the left occipito-temporal areas, namely BA37 and BA20. Category-related ERP differences were also observed in the amplitudes of the later centro-parietal N400, posterior P300 and anterior LP components. Behavioral responses to words denoting fauna were more accurate than to words denoting flora.
Overall, it seems that it was easier to access the lexical properties of fauna, probably because of their biologically relevant status. The results are discussed in the light of the possible role played by different factors.
电生理、血液动力学和神经心理学研究为不同语义范畴（如动物、工具、动作）的词在大脑中的表现存在差异提供了证据。本研究旨在探讨语义领域是否可能独立于其他因素影响 ERP 成分的振幅和潜伏期。
16 名志愿者参与了一项词汇判断任务（词/非词辨别），涉及 100 个单词（动植物名称），记录了他们的脑电图。这项任务使我们能够独立于任务要求评估属于不同类别的词（动物与植物）之间的处理差异。所有刺激在长度、出现频率、熟悉度和形象化方面都是平衡的。对感兴趣的 ERP 差值波进行低分辨率电磁断层成像（LORETA）。
我们的研究结果表明，这两个类别早在刺激后 200 毫秒就被区分出来，对植物名称的反应比左枕颞区（即 BA37 和 BA20）更大。在随后的中央顶叶 N400、后顶叶 P300 和前额 LP 成分的振幅中也观察到与类别相关的 ERP 差异。表示动物的词的行为反应比表示植物的词更准确。
总的来说，似乎更容易获得动物的词汇属性，这可能是因为它们具有生物学相关性。结果在可能发挥作用的不同因素的背景下进行了讨论。
