Horki P, Bauernfeind G, Schippinger W, Pichler G, Müller-Putz G R
Institute of Neural Engineering, Graz University of Technology, Stremayrgasse 16/IV, 8010 Graz, Austria.
Department of Otolaryngology, Hannover Medical School, Hannover, Germany; Cluster of Excellence "Hearing4all", Hannover, Germany; Institute of Neural Engineering, Graz University of Technology, Stremayrgasse 16/IV, 8010 Graz, Austria.
J Neurosci Methods. 2016 Sep 1;270:165-176. doi: 10.1016/j.jneumeth.2016.06.015. Epub 2016 Jun 18.
Two challenges need to be addressed before bringing non-motor mental tasks for brain-computer interface (BCI) control to persons in a minimally conscious state (MCS), who can be behaviorally unresponsive even when proven to be consciously aware: first, keeping the cognitive demands as low as possible so that they could be fulfilled by persons with MCS. Second, increasing the control of experimental protocol (i.e. type and timing of the task performance).
The goal of this study is twofold: first goal is to develop an experimental paradigm that can facilitate the performance of brain-teasers (e.g. mental subtraction and word generation) on the one hand, and can increase the control of experimental protocol on the other hand. The second goal of this study is to exploit the similar findings for mentally attending to someone else's verbal performance of brain-teaser tasks and self-performing the same tasks to setup an online BCI, and to compare it in healthy participants to the current "state-of-the-art" motor imagery (MI, sports).
The response accuracies for the best performing healthy participants indicate that selective attention to verbal performance of mental subtraction (SUB) is a viable alternative to the MI. Time-frequency analysis of the SUB task in one participant with MCS did not reveal any significant (p<0.05) EEG changes, whereas imagined performance of one sport of participants' choice (SPORT) revealed task-related EEG changes over neurophysiological plausible cortical areas.
We found that mentally attending to someone else's verbal performance of brain-teaser tasks leads to similar results as in self-performing the same tasks.
In this work we demonstrated that a single auditory selective attention task (i.e. mentally attending to someone else's verbal performance of mental subtraction) can modulate both induced and evoked changes in EEG, and be used for yes/no communication in an auditory scanning paradigm.
在将用于脑机接口（BCI）控制的非运动性心理任务应用于处于最低意识状态（MCS）的患者之前，需要解决两个挑战。即使已被证明有意识，但这些患者在行为上可能没有反应：第一，将认知需求尽可能降低，以便MCS患者能够完成这些任务。第二，加强对实验方案的控制（即任务执行的类型和时间）。
本研究的目标有两个：第一个目标是开发一种实验范式，一方面可以促进脑筋急转弯任务（如心算和单词生成）的执行，另一方面可以加强对实验方案的控制。本研究的第二个目标是利用在心理上关注他人进行脑筋急转弯任务的言语表现和自己执行相同任务的类似发现来建立一个在线BCI，并在健康参与者中将其与当前的“最先进”运动想象（MI，运动）进行比较。
表现最佳的健康参与者的反应准确率表明，选择性关注心算（SUB）的言语表现是MI的一个可行替代方案。对一名MCS患者的SUB任务进行时频分析未发现任何显著（p<0.05）的脑电图变化，而对参与者选择的一项运动（SPORT）的想象表现则在神经生理学上合理的皮层区域显示出与任务相关的脑电图变化。
我们发现，心理上关注他人进行脑筋急转弯任务的言语表现会产生与自己执行相同任务类似的结果。
在这项工作中，我们证明了单一的听觉选择性注意任务（即心理上关注他人的心算言语表现）可以调节脑电图的诱发和诱发性变化，并可用于听觉扫描范式中的是/否通信。
