The Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan 5290002, Israel; The Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
The Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan 5290002, Israel.
Neuroimage. 2023 Aug 15;277:120255. doi: 10.1016/j.neuroimage.2023.120255. Epub 2023 Jul 5.
The experience of the self as an embodied agent in the world is an essential aspect of human consciousness. This experience arises from the feeling of control over one's bodily actions, termed the Sense of Agency, and the feeling that the body belongs to the self, Body Ownership. Despite longstanding philosophical and scientific interest in the relationship between the body and brain, the neural systems involved in Body Ownership and Sense of Agency, and especially their interactions, are not yet understood. In this preregistered study using the Moving Rubber Hand Illusion inside an MR-scanner, we aimed to uncover the relationship between Body Ownership and Sense of Agency in the human brain. Importantly, by using both visuomotor and visuotactile stimulations and measuring online trial-by-trial fluctuations in the illusion magnitude, we were able to disentangle brain systems related to objective sensory stimulation and subjective judgments of the bodily-self. Our results indicate that at both the behavioral and neural levels, Body Ownership and Sense of Agency are strongly interrelated. Multisensory regions in the occipital and fronto-parietal regions encoded convergence of sensory stimulation conditions. The subjective judgments of the bodily-self were related to BOLD fluctuations in the Somatosensory cortex and in regions not activated by the sensory conditions, such as the insular cortex and precuneus. Our results highlight the convergence of multisensory processing in specific neural systems for both Body Ownership and Sense of Agency with partially dissociable regions for subjective judgments in regions of the Default Mode Network.
作为一个在世界上有实体存在的主体的自我体验是人类意识的一个重要方面。这种体验来自于对自己身体动作的控制感，即主体感，以及身体属于自我的感觉，即身体所有权。尽管人们对身体和大脑之间的关系有着长期的哲学和科学兴趣，但涉及身体所有权和主体感的神经系统，尤其是它们之间的相互作用，仍未被理解。在这项使用磁共振扫描仪内的移动橡胶手错觉进行的预先注册研究中，我们旨在揭示人类大脑中身体所有权和主体感之间的关系。重要的是，通过使用视觉运动和视触觉刺激，并测量错觉强度的在线逐次波动，我们能够区分与客观感觉刺激和对身体自我的主观判断相关的大脑系统。我们的结果表明，在行为和神经水平上，身体所有权和主体感都密切相关。枕叶和额顶叶区域的多感觉区域编码了感觉刺激条件的收敛。对身体自我的主观判断与体感皮层和未被感觉条件激活的区域（如岛叶和楔前叶）的 BOLD 波动有关。我们的结果强调了特定的多感觉处理在身体所有权和主体感的特定神经系统中的收敛，而在默认模式网络的区域中，对主观判断的部分分离。
