Okamoto Yuko, Kitada Ryo, Kochiyama Takanori, Miyahara Motohide, Naruse Hiroaki, Sadato Norihiro, Okazawa Hidehiko, Kosaka Hirotaka
Waseda Institute for Advanced Study (WIAS), Waseda University, Tokyo, 169-0051, Japan.
Graduate School of Intercultural Studies, Kobe University, Kobe, 657-8501, Japan.
Neuroimage Rep. 2021 Aug 20;1(4):100046. doi: 10.1016/j.ynirp.2021.100046. eCollection 2021 Dec.
Visual self-body recognition is one of the fundamental cognitive functions, and a major contributor to social development. Previous studies have shown that body identity judgement becomes difficult when subjects viewed their hand from a third-person perspective, and that this perspective effect was not observed when viewing the hand of another person, indicating that there are brain regions which are more strongly influenced by the perspective of one's own body than the body of another person. In this study, we aimed to depict the brain network contributing to the integration of perspective and identity of human bodies. We conducted a functional magnetic resonance imaging experiment where 29 participants observed their own or someone else's hand from first- and third-person perspectives. In the univariate analysis, none of the brain regions showed an interaction between perspective and body identity. However, in the searchlight and region-of-interest multivoxel pattern analysis (MVPA), decoding accuracies of self-hand from a first-person vs. those from a third-person perspective were higher than the decoding accuracies of other-hand from a first-person perspective vs. those from a third-person perspective in the early visual cortex. In addition, psychophysiological interaction analysis revealed a stronger effect of perspective of the self-hand than the other-hand condition in connectivity between the lateral occipito-temporal cortex and the early visual cortex, overlapped with the region depicted by MVPA. Our results suggest that the specific link between self-hand and first-person perspective is associated with identity-dependent perspective representations of the early visual cortex and functional connectivity between the early visual cortex and lateral occipito-temporal cortex, elucidating the nature of self-body recognition.
视觉自我身体识别是基本的认知功能之一，也是社会发展的主要促成因素。先前的研究表明，当受试者从第三人称视角观察自己的手时，身体身份判断会变得困难，而在观察他人的手时则未观察到这种视角效应，这表明存在一些脑区，与他人身体相比，自身身体的视角对其影响更强。在本研究中，我们旨在描绘有助于人体视角与身份整合的脑网络。我们进行了一项功能磁共振成像实验，29名参与者从第一人称和第三人称视角观察自己或他人的手。在单变量分析中，没有脑区显示出视角与身体身份之间的相互作用。然而，在探照灯和感兴趣区域多体素模式分析（MVPA）中，在早期视觉皮层中，从第一人称视角与第三人称视角对自己手的解码准确率高于从第一人称视角与第三人称视角对他人手的解码准确率。此外，心理生理交互分析显示，在枕颞外侧皮层与早期视觉皮层之间的连接中，自己手的视角效应比他人手的情况更强，且与MVPA描绘的区域重叠。我们的结果表明，自己手与第一人称视角之间的特定联系与早期视觉皮层中依赖身份的视角表征以及早期视觉皮层与枕颞外侧皮层之间的功能连接有关，阐明了自我身体识别的本质。
