Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada.
Biomed Phys Eng Express. 2020 Apr 15;6(3):035024. doi: 10.1088/2057-1976/ab872c.
Motor imagery can be used as an adjunct to traditional stroke rehabilitation therapies for individuals who have hand and arm impairment resulting from their stroke. The provision of neurofeedback during motor imagery allows individuals to receive real time information regarding their motor imagery-related brain activity. However, the equipment required to administer this feedback is expensive and largely inaccessible to many of the individuals who could benefit from it. Available EEG-based technology provides an accessible, low-cost, wireless alternative to traditional neurofeedback methods, with the tradeoff of lower gain and channel count resulting in reduced signal quality. This study investigated the efficacy of this wireless technology for the provision of motor imagery-related neurofeedback.
Twenty-eight healthy individuals participated in a 2-group, double-blinded study which involved imagining performing a unimanual button pressing task while receiving neurofeedback that is either a direct transform of their motor imagery-related brain activity (i.e., real) or is related to someone else's brain activity (i.e., sham). The change in amplitude of 15-30 Hz (beta) rhythmic brain activity elicited during the task blocks was calculated and analyzed across sessions and groups.
We found that individuals who received real neurofeedback showed a statistically significant positive trajectory in modulating the amplitude of the beta rhythm across sessions, while those who received sham feedback showed a negative trajectory. Our results did not indicate a trend of increased lateralization across sessions, as has been shown in previous studies.
Our main findings replicated previous results with research-grade equipment indicating that there is potential for introducing this wireless technology for the provision of neurofeedback. Given the marginal longitudinal effect of neurofeedback in our study, further study is required to address the limitations associated with this technology before our protocol can be implemented in a clinical setting.
运动想象可作为传统中风康复疗法的辅助手段，适用于因中风而手部和手臂受损的个体。在运动想象过程中提供神经反馈，可让个体实时了解与运动想象相关的大脑活动。然而，提供这种反馈所需的设备昂贵，且对许多可能受益于此的个体来说，难以获得。现有的基于脑电图的技术为传统神经反馈方法提供了一种可及、低成本、无线的替代方案，但其增益和通道数量较低，导致信号质量降低。本研究旨在调查这种无线技术在提供运动想象相关神经反馈方面的效果。
28 名健康个体参加了一项 2 组、双盲研究，其中涉及在想象执行单手按钮按压任务时接收神经反馈，该反馈是对其运动想象相关大脑活动的直接转换（即真实）或与他人大脑活动相关（即假）。在任务块期间，计算并分析了 15-30 Hz（β）节律性脑活动幅度的变化，并在各次会议和组之间进行分析。
我们发现，接受真实神经反馈的个体在调节β节律幅度方面表现出具有统计学意义的积极轨迹，而接受虚假反馈的个体则表现出消极轨迹。我们的结果没有显示出跨次会议的侧化趋势增加，这与之前的研究结果一致。
我们的主要发现复制了使用研究级设备的先前结果，表明有可能引入这种无线技术来提供神经反馈。鉴于神经反馈在我们的研究中仅具有边际纵向效应，在将我们的方案实施到临床环境之前，还需要进一步研究以解决与该技术相关的限制。
