Service neuro-diagnostique et neuro-interventionnel DISIM, University Hospitals of Geneva, Switzerland.
Department of Radiology and Medical Informatics, University of Geneva, Switzerland; Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Switzerland.
Neuroimage. 2013 Nov 1;81:243-252. doi: 10.1016/j.neuroimage.2013.05.019. Epub 2013 May 16.
Recent fMRI studies demonstrated that functional connectivity is altered following cognitive tasks (e.g., learning) or due to various neurological disorders. We tested whether real-time fMRI-based neurofeedback can be a tool to voluntarily reconfigure brain network interactions. To disentangle learning-related from regulation-related effects, we first trained participants to voluntarily regulate activity in the auditory cortex (training phase) and subsequently asked participants to exert learned voluntary self-regulation in the absence of feedback (transfer phase without learning). Using independent component analysis (ICA), we found network reconfigurations (increases in functional network connectivity) during the neurofeedback training phase between the auditory target region and (1) the auditory pathway; (2) visual regions related to visual feedback processing; (3) insula related to introspection and self-regulation and (4) working memory and high-level visual attention areas related to cognitive effort. Interestingly, the auditory target region was identified as the hub of the reconfigured functional networks without a-priori assumptions. During the transfer phase, we again found specific functional connectivity reconfiguration between auditory and attention network confirming the specific effect of self-regulation on functional connectivity. Functional connectivity to working memory related networks was no longer altered consistent with the absent demand on working memory. We demonstrate that neurofeedback learning is mediated by widespread changes in functional connectivity. In contrast, applying learned self-regulation involves more limited and specific network changes in an auditory setup intended as a model for tinnitus. Hence, neurofeedback training might be used to promote recovery from neurological disorders that are linked to abnormal patterns of brain connectivity.
最近的 fMRI 研究表明,功能连接在认知任务(例如学习)之后或由于各种神经障碍而发生改变。我们测试了基于实时 fMRI 的神经反馈是否可以作为一种自愿重新配置大脑网络相互作用的工具。为了将与学习相关的效应与与调节相关的效应分开,我们首先训练参与者自愿调节听觉皮层的活动(训练阶段),然后要求参与者在没有反馈的情况下施加习得的自愿自我调节(无学习的转移阶段)。使用独立成分分析(ICA),我们发现在神经反馈训练阶段,听觉目标区域与(1)听觉通路;(2)与视觉反馈处理相关的视觉区域;(3)与内省和自我调节相关的脑岛;(4)与认知努力相关的工作记忆和高级视觉注意力区域之间存在网络重新配置(功能网络连接增加)。有趣的是,听觉目标区域被确定为重新配置的功能网络的枢纽,而无需先验假设。在转移阶段,我们再次在听觉和注意力网络之间发现了特定的功能连接重新配置,证实了自我调节对功能连接的特定影响。与工作记忆相关的网络的功能连接不再改变,这与工作记忆的需求无关。我们证明神经反馈学习是由功能连接的广泛变化介导的。相比之下,在听觉设置中应用习得的自我调节涉及更有限和特定的网络变化,听觉设置旨在作为耳鸣的模型。因此,神经反馈训练可能用于促进与异常大脑连接模式相关的神经障碍的恢复。