INESC TEC - Institute for Systems and Computer Engineering, Technology and Science, and Faculty of Engineering, University of Porto, Porto, Portugal.
Institute for Systems and Robotics - Lisboa, and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
PLoS One. 2023 Sep 27;18(9):e0291528. doi: 10.1371/journal.pone.0291528. eCollection 2023.
Training motor imagery (MI) and motor observation (MO) tasks is being intensively exploited to promote brain plasticity in the context of post-stroke rehabilitation strategies. This may benefit from the use of closed-loop neurofeedback, embedded in brain-computer interfaces (BCI's) to provide an alternative non-muscular channel, which may be further augmented through embodied feedback delivered through virtual reality (VR). Here, we used functional magnetic resonance imaging (fMRI) in a group of healthy adults to map brain activation elicited by an ecologically-valid task based on a VR-BCI paradigm called NeuRow, whereby participants perform MI of rowing with the left or right arm (i.e., MI), while observing the corresponding movement of the virtual arm of an avatar (i.e., MO), on the same side, in a first-person perspective. We found that this MI-MO task elicited stronger brain activation when compared with a conventional MI-only task based on the Graz BCI paradigm, as well as to an overt motor execution task. It recruited large portions of the parietal and occipital cortices in addition to the somatomotor and premotor cortices, including the mirror neuron system (MNS), associated with action observation, as well as visual areas related with visual attention and motion processing. Overall, our findings suggest that the virtual representation of the arms in an ecologically-valid MI-MO task engage the brain beyond conventional MI tasks, which we propose could be explored for more effective neurorehabilitation protocols.
训练运动想象（MI）和运动观察（MO）任务正被广泛应用于促进脑卒中康复策略中的大脑可塑性。这可能受益于闭环神经反馈的使用，嵌入脑机接口（BCI）中提供替代非肌肉通道，通过虚拟现实（VR）提供的体现反馈进一步增强。在这里，我们使用功能磁共振成像（fMRI）在一组健康成年人中绘制了基于 VR-BCI 范式的生态有效任务引起的大脑激活图，该范式称为 NeuRow，参与者通过左或右臂进行 MI（即 MI），同时观察到虚拟手臂的相应运动。在第一人称视角中，化身（即 MO）在同一边。我们发现，与基于 Graz BCI 范式的传统 MI 任务相比，以及与明显的运动执行任务相比，这种 MI-MO 任务引起了更强的大脑激活。它除了躯体运动和运动前皮质外，还招募了大量的顶叶和枕叶皮质，包括与动作观察相关的镜像神经元系统（MNS），以及与视觉注意力和运动处理相关的视觉区域。总的来说，我们的发现表明，生态有效 MI-MO 任务中手臂的虚拟表示超越了传统的 MI 任务，我们提出可以探索更有效的神经康复方案。
