Tokimoto Shingo, Tokimoto Naoko
Department of English Language Studies, Mejiro University, Tokyo, Japan.
Department of Policy Management, Shobi University, Kawagoe, Japan.
Front Psychol. 2018 Aug 29;9:1574. doi: 10.3389/fpsyg.2018.01574. eCollection 2018.
This study examines the neural substrate of perspective-taking by analyzing the electroencephalographic (EEG) activity elicited by the auditory comprehension of sentences for which the comprehender had to adopt the perspective of the person described in them. Recent studies suggest that the ability of perspective-taking can be an integrative function of temporal and spatial information processing. We thus examined the independence and possible interaction of human perspective shifts and temporal perspective-taking by utilizing Japanese subsidiary verbs for giving, namely and . We manipulated human perspective shifts and temporal perspective-taking independently in experimental sentences by syntactically changing the subject and the object between the speaker and a third person, while we manipulated the tense to be past or non-past tense via sentence-final particles (non-past/past). The EEG analyses via electrodes indicated the suppression of the β band for human perspective shifts in sentences in non-past tense and the absence of such suppression in sentences in past tense. The analyses for the clusters of independent components indicated β suppression for past tense against non-past tense in sentences without a human perspective shift. This response pattern suggests a close relationship between human perspective shifting and temporal perspective-taking. The β suppression for the human perspective shift in our experiment can be understood as a replication of the previous EEG findings observed for perspective-taking in the presentation of visual images. The preceding findings and our result suggest that the ability or the function of perspective-taking is not specific to the modality. Furthermore, the generator of the β suppression for past tense against non-past tense without human perspective shifting was localized in the precuneus, which is consistent with recent findings indicating that the precuneus is deeply involved in time perception.
本研究通过分析理解者必须采取句子中所描述人物视角时，对句子进行听觉理解所引发的脑电图（EEG）活动，来探究换位思考的神经基础。近期研究表明，换位思考能力可能是时间和空间信息处理的一种综合功能。因此，我们利用日语中表示给予的补助动词，即“てる”和“てある”，来检验人类视角转换与时间换位思考的独立性及可能的相互作用。我们通过在实验句子中句法上改变说话者和第三人之间的主语和宾语，来独立操纵人类视角转换和时间换位思考，同时通过句末助词“よ”（非过去/过去）来操纵时态为过去或非过去时态。通过电极进行的EEG分析表明，非过去时态句子中人类视角转换时β波段受到抑制，而过去时态句子中则不存在这种抑制。对独立成分簇的分析表明，在没有人类视角转换的句子中，过去时态相对于非过去时态存在β抑制。这种反应模式表明人类视角转换与时间换位思考之间存在密切关系。我们实验中人类视角转换时的β抑制可以理解为是对先前在视觉图像呈现中换位思考所观察到的EEG结果的重复。先前的研究结果和我们的结果表明，换位思考的能力或功能并非特定于某种模态。此外，在没有人类视角转换的情况下，过去时态相对于非过去时态的β抑制的产生源位于楔前叶，这与最近表明楔前叶深度参与时间感知的研究结果一致。
