Department of Psychology, Hokkaido University, Sapporo 060-0810, Japan.
Department of Psychology, Hokkaido University, Sapporo 060-0810, Japan
eNeuro. 2023 Feb 10;10(2). doi: 10.1523/ENEURO.0332-22.2023. Print 2023 Feb.
The sense of body ownership, defined as the sensation that one's body belongs to oneself, is a fundamental component of bodily self-consciousness. Several studies have shown the importance of multisensory integration for the emergence of the sense of body ownership, together with the involvement of the parieto-premotor and extrastriate cortices in bodily awareness. However, whether the sense of body ownership elicited by different sources of signal, especially visuotactile and visuomotor inputs, is represented by common neural patterns remains to be elucidated. We used functional magnetic resonance imaging (fMRI) to investigate the existence of neural correlates of the sense of body ownership independent of the sensory modalities. Participants received tactile stimulation or executed finger movements while given synchronous and asynchronous visual feedback of their hand. We used multivoxel patterns analysis (MVPA) to decode the synchronous and asynchronous conditions with cross-classification between two modalities: the classifier was first trained in the visuotactile sessions and then tested in the visuomotor sessions, and vice versa. Regions of interest (ROIs)-based and searchlight analyses revealed significant above-chance cross-classification accuracies in the bilateral intraparietal sulcus (IPS), the bilateral ventral premotor cortex (PMv), and the left extrastriate body area (EBA). Moreover, we observed a significant positive correlation between the cross-classification accuracy in the left PMv and the difference in subjective ratings of the sense of body ownership between the synchronous and asynchronous conditions. Our findings revealed the neural representations of the sense of body ownership in the IPS, PMv, and EBA that is invariant to the sensory modalities.
躯体所有权意识是躯体自我意识的基本组成部分,它是指一个人对自己身体的感觉。几项研究表明,多感觉整合对于躯体所有权意识的出现很重要,同时涉及顶叶-运动前皮质和额-外纹状体皮质对躯体知觉的参与。然而,不同信号源(尤其是视触和视动输入)引起的躯体所有权感觉是否由共同的神经模式来表示,仍有待阐明。我们使用功能磁共振成像(fMRI)来研究与感觉模态无关的躯体所有权的神经关联。参与者在手接受触觉刺激或执行手指运动时,同时给予手部的同步和异步视觉反馈。我们使用多体素模式分析(MVPA)来对两种模态之间的同步和异步条件进行解码:分类器首先在视触觉会话中进行训练,然后在视动会话中进行测试,反之亦然。基于感兴趣区域(ROI)和搜索灯分析显示,双侧顶内沟(IPS)、双侧腹侧运动前皮质(PMv)和左侧额-外纹状体躯体区(EBA)中存在显著高于随机水平的跨分类准确性。此外,我们观察到左侧 PMv 中的跨分类准确性与同步和异步条件之间躯体所有权感觉的主观评分差异之间存在显著的正相关。我们的研究结果揭示了 IPS、PMv 和 EBA 中躯体所有权意识的神经表示,这种表示与感觉模态无关。