隐喻加工脑区的关联因素

在隐喻理解的神经成像研究中，以往研究者没有足够重视这一认知过程中隐喻本身和大脑工作机制的复杂性，并且在研究方法上也存在不足，由此导致了隐喻理解的左脑、右脑及全脑优势之争。需要注意的是，隐喻理解是非常复杂的认知过程，涉及众多环节，必然会受到隐喻本身特性、个体认知差异以及大脑信息整合方式等诸多因素的影响，包括隐喻的新颖程度、隐喻的形象化程度、隐喻表达的多模态性、个体的智能程度、个体对于隐喻的熟悉程度、不同模态和不同语义范畴的隐喻信息整合方式等。同时，隐喻理解的上述复杂性决定了这一理解过程不可能由单一脑区独立完成，它既涉及相应功能区的加工，也涉及相关脑区的整合。只有分工合作，进行全脑总动员，才能保证隐喻信息得到正确而又迅速的加工。

Factors Related to Metaphor-Processing Areas of the Brain

As one of the most important perspectives to understand the world, metaphor interpretation has long been concerned by researchers in cognitive fields. The development of advanced neuroimaging technologies, such as fMRI and ERP, which facilitate observing the process of metaphor comprehension in the brain, have all the more pushed this research forward. However, the conflicting conclusions drawn by different researchers confuse our view about the brain areas involving metaphor processing. Currently, there are three prevailing views, namely, the right brain theory, the left brain theory and the whole brain theory, which arouse our reflection. We have found out that there is something in each conclusion while there do exist contradictions between these conclusions. The reasons for the contradictions lie in the following two aspects: (1) There are some drawbacks in the researchers' view that metaphor processing simply involves some particular area in the brain|(2) There are still some vulnerabilities in their experimental designs. It should be noted that metaphor comprehension, i.e. the input, extraction, processing and integration of metaphorical information, is a quite complicated process, which is affected by many factors, including the characteristics of metaphor, the difference of individual processing, the way of information integration in the brain, and so on. That is why we cannot take it for granted that we have seen the whole picture of metaphor processing in the brain while we have only found out some of the aspects of the processing. Metaphor comprehension is such a complicated process that it cannot be completed by a single brain area. As an external stimulus, the novelty, visualization and multi-modality of metaphor itself may have influence on the processing. And the difference between individuals, including their intelligence and their familiarity with a given metaphor may also have effect on the processing. Besides, the way our brain integrates the metaphor information likewise presents the versatility and complexity of metaphor processing from input, extraction, processing and integration. Based on the experimental results of the previous researchers, it is concluded in the paper that the brain processing of metaphorical language has its own special features but it also shares the common features of general language processing. As far as a normal individual is concerned, the classical brain areas of language processing are situated in the left hemisphere but the right hemisphere will be involved in the processing of metaphorical language. The involvement of the right hemisphere in the metaphor processing is determined by the novelty and visuality of a metaphor, that is, the more novel and more visual a metaphor is, the more probably the right brain participates in the processing. On the contrary, the more conventionalized a metaphor is, the less involved the right brain is. The familiarity with metaphor is the norm for the individual to identify whether it is a novel or a conventional metaphor being processed in the brain. To the individual, the more unfamiliar he/she is with the metaphor, the more novel it is. On the contrary, the more familiar he/she is with the metaphor, the more conventional it is. However, to those groups of people as young children whose brains are under development, old people whose brains are degenerated, or patients whose brain is injured, it is more difficult for them to understand a metaphor and then it is most likely for them to consume more cognitive resources, which leads to a larger scale of activation. The multi-model input of metaphor and the way of information integration in the brain also determine that the metaphor processing cannot be completed by a single brain area. Instead, it should be done from the input of metaphorical information through different sensory channels, to the extraction and processing by corresponding functional brain areas, and then to the integration in the whole brain network. Therefore, metaphor comprehension is such a complicated process that it involves the cooperation of the related brain areas, including the processing of corresponding functional brain areas and the blending of related brain areas in the neural network. Although some brain area or areas takes a more active role in a certain cognitive task, the processing still needs the cooperation with other areas involved in the whole brain network to guarantee the prompt and correct processing of metaphorical information.