Assadollahi Ramin, Rockstroh Brigitte S
Department of Psychology, University of Konstanz, 78457 Konstanz, Germany.
BMC Neurosci. 2008 Jul 21;9:69. doi: 10.1186/1471-2202-9-69.
A verb's argument structure defines the number and relationships of participants needed for a complete event. One-argument (intransitive) verbs require only a subject to make a complete sentence, while two- and three-argument verbs (transitives and ditransitives) normally take direct and indirect objects. Cortical responses to verbs embedded into sentences (correct or with syntactic violations) indicate the processing of the verb's argument structure in the human brain. The two experiments of the present study examined whether and how this processing is reflected in distinct spatio-temporal cortical response patterns to isolated verbs and/or verbs presented in minimal context.
The magnetoencephalogram was recorded while 22 native German-speaking adults saw 130 German verbs, presented one at a time for 150 ms each in experiment 1. Verb-evoked electromagnetic responses at 250 - 300 ms after stimulus onset, analyzed in source space, were higher in the left middle temporal gyrus for verbs that take only one argument, relative to two- and three-argument verbs. In experiment 2, the same verbs (presented in different order) were preceded by a proper name specifying the subject of the verb. This produced additional activation between 350 and 450 ms in or near the left inferior frontal gyrus, activity being larger and peaking earlier for one-argument verbs that required no further arguments to form a complete sentence.
Localization of sources of activity suggests that the activation in temporal and frontal regions varies with the degree by which representations of an event as a part of the verbs' semantics are completed during parsing.
动词的论元结构定义了一个完整事件所需参与者的数量和关系。单论元（不及物）动词只需要一个主语就能构成一个完整的句子，而双论元和三论元动词（及物动词和双及物动词）通常需要直接宾语和间接宾语。大脑皮层对嵌入句子中的动词（正确的或有句法违规的）的反应表明了人类大脑中动词论元结构的处理过程。本研究的两个实验考察了这种处理过程是否以及如何在对孤立动词和/或在最小语境中呈现的动词的不同时空皮层反应模式中得到体现。
在实验1中，22名以德语为母语的成年人观看130个德语动词时记录了脑磁图，每个动词每次呈现150毫秒，依次呈现。在源空间分析刺激开始后250 - 300毫秒时动词诱发的电磁反应，单论元动词在左颞中回的反应相对于双论元和三论元动词更高。在实验2中，相同的动词（以不同顺序呈现）之前有一个指定动词主语的专有名词。这在350至450毫秒之间在左额下回或其附近产生了额外的激活，对于不需要进一步论元就能构成完整句子的单论元动词，激活更大且峰值出现得更早。
活动源的定位表明，颞叶和额叶区域的激活随在句法分析过程中作为动词语义一部分的事件表征完成程度而变化。
