Banca Paula, Sousa Teresa, Duarte Isabel Catarina, Castelo-Branco Miguel
Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, and Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Portugal. PhD Programme in Experimental Biology and Biomedicine, Center for Neuroscience and Cell Biology, University of Coimbra, Portugal.
J Neural Eng. 2015 Dec;12(6):066003. doi: 10.1088/1741-2560/12/6/066003. Epub 2015 Sep 24.
Current approaches in neurofeedback/brain-computer interface research often focus on identifying, on a subject-by-subject basis, the neural regions that are best suited for self-driven modulation. It is known that the hMT+/V5 complex, an early visual cortical region, is recruited during explicit and implicit motion imagery, in addition to real motion perception. This study tests the feasibility of training healthy volunteers to regulate the level of activation in their hMT+/V5 complex using real-time fMRI neurofeedback and visual motion imagery strategies.
We functionally localized the hMT+/V5 complex to further use as a target region for neurofeedback. An uniform strategy based on motion imagery was used to guide subjects to neuromodulate hMT+/V5.
We found that 15/20 participants achieved successful neurofeedback. This modulation led to the recruitment of a specific network as further assessed by psychophysiological interaction analysis. This specific circuit, including hMT+/V5, putative V6 and medial cerebellum was activated for successful neurofeedback runs. The putamen and anterior insula were recruited for both successful and non-successful runs.
Our findings indicate that hMT+/V5 is a region that can be modulated by focused imagery and that a specific cortico-cerebellar circuit is recruited during visual motion imagery leading to successful neurofeedback. These findings contribute to the debate on the relative potential of extrinsic (sensory) versus intrinsic (default-mode) brain regions in the clinical application of neurofeedback paradigms. This novel circuit might be a good target for future neurofeedback approaches that aim, for example, the training of focused attention in disorders such as ADHD.
神经反馈/脑机接口研究中的当前方法通常侧重于逐个受试者地识别最适合自我驱动调节的神经区域。众所周知，hMT+/V5复合体是早期视觉皮层区域，除了真实运动感知外，在明确和隐含的运动想象过程中也会被激活。本研究测试了使用实时功能磁共振成像神经反馈和视觉运动想象策略训练健康志愿者调节其hMT+/V5复合体激活水平的可行性。
我们对hMT+/V5复合体进行功能定位，以便进一步用作神经反馈的目标区域。基于运动想象的统一策略被用来指导受试者对hMT+/V5进行神经调节。
我们发现20名参与者中有15名成功实现了神经反馈。通过心理生理交互分析进一步评估，这种调节导致了一个特定网络的激活。这个特定的回路，包括hMT+/V5、假定的V6和内侧小脑，在成功的神经反馈过程中被激活。壳核和前岛叶在成功和未成功的过程中均被激活。
我们的研究结果表明，hMT+/V5是一个可以通过聚焦想象进行调节的区域，并且在视觉运动想象过程中会募集一个特定的皮质-小脑回路，从而实现成功的神经反馈。这些发现有助于在神经反馈范式的临床应用中，就外在（感觉）与内在（默认模式）脑区的相对潜力展开辩论。这个新的回路可能是未来神经反馈方法的一个良好目标，例如旨在训练注意力缺陷多动障碍等疾病中的集中注意力。
