Human Sensation of Transcranial Electric Stimulation.
Human Sensation of Transcranial Electric Stimulation.
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人类对经颅电刺激的感觉。
DOI：
10.1038/s41598-019-51792-8
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发表时间：
2019
影响因子：
4.6
通讯作者：
Xu,Yuchen
中科院分区：
文献类型：
--
作者：
Zeng,Fan-Gang;Tran,Phillip;Richardson,Matthew;Sun,Shuping;Xu,Yuchen
无创经颅电刺激越来越多地被用作一种有利的治疗替代方案，其可以激活深部组织，同时避免药物副作用。然而，经颅电刺激不仅激活深部组织的证据有限，而且其诱发的人类感觉也未得到充分研究，经常被视为安慰剂或次要效应。通过系统地表征由经颅交流刺激引起的人类感觉，我们观察到不仅刺激频率和电极位置对听觉和视觉的依赖性，而且更广泛地存在从触摸和振动到疼痛和压力的躯体感觉。我们发现，一般单调的输入输出功能在阈上水平，往往是多种类型的感觉同时发生在同一个电刺激的反应。我们进一步使用嵌入在人工耳蜗植入体中的记录电路来直接和客观地测量到达听神经的经颅电刺激的量，听神经是位于颅骨的密质骨中的深部颅内目标。我们发现了使用耳道电极和低频（<300 Hz）正弦波的最佳配置，该配置向听神经输送最大约1%的经颅电流，即使在聋耳中也足以产生声音感觉。我们的研究结果表明，由于神经元固有的电特性的频率共振需要探索有针对性的深部脑刺激和新的脑机接口。
Noninvasive transcranial electric stimulation is increasingly being used as an advantageous therapy alternative that may activate deep tissues while avoiding drug side-effects. However, not only is there limited evidence for activation of deep tissues by transcranial electric stimulation, its evoked human sensation is understudied and often dismissed as a placebo or secondary effect. By systematically characterizing the human sensation evoked by transcranial alternating-current stimulation, we observed not only stimulus frequency and electrode position dependencies specific for auditory and visual sensation but also a broader presence of somatic sensation ranging from touch and vibration to pain and pressure. We found generally monotonic input-output functions at suprathreshold levels, and often multiple types of sensation occurring simultaneously in response to the same electric stimulation. We further used a recording circuit embedded in a cochlear implant to directly and objectively measure the amount of transcranial electric stimulation reaching the auditory nerve, a deep intercranial target located in the densest bone of the skull. We found an optimal configuration using an ear canal electrode and low-frequency (<300 Hz) sinusoids that delivered maximally ~1% of the transcranial current to the auditory nerve, which was sufficient to produce sound sensation even in deafened ears. Our results suggest that frequency resonance due to neuronal intrinsic electric properties need to be explored for targeted deep brain stimulation and novel brain-computer interfaces.