title: Stimulating the Comfort of Textile Electrodes in Wearable Neuromuscular Electrical Stimulation.
abstract: Textile electrodes are becoming an attractive means in the facilitation of surface electrical stimulation. However, the stimulation comfort of textile electrodes and the mechanism behind stimulation discomfort is still unknown. In this study, a textile stimulation electrode was developed using conductive fabrics and then its impedance spectroscopy, stimulation thresholds, and stimulation comfort were quantitatively assessed and compared with those of a wet textile electrode and a hydrogel electrode on healthy subjects. The equivalent circuit models and the finite element models of different types of electrode were built based on the measured impedance data of the electrodes to reveal the possible mechanism of electrical stimulation pain. Our results showed that the wet textile electrode could achieve similar stimulation performance as the hydrogel electrode in motor threshold and stimulation comfort. However, the dry textile electrode was found to have very low pain threshold and induced obvious cutaneous painful sensations during stimulation, in comparison to the wet and hydrogel electrodes. Indeed, the finite element modeling results showed that the activation function along the z direction at the depth of dermis epidermis junction of the dry textile electrode was significantly larger than that of the wet and hydrogel electrodes, thus resulting in stronger activation of pain sensing fibers. Future work will be done to make textile electrodes have similar stimulation performance and comfort as hydrogel electrodes.
authors.affiliation: Key Laboratory of Human-Machine Intelligence-Synergy Systems of Chinese Academy of Sciences, Shenzhen 518055, China. hui.zhou@siat.ac.cn.|Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. hui.zhou@siat.ac.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Shenzhen Engineering Lab for Brain Activity Mapping Technologies, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. luyi@siat.ac.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Key Laboratory of Human-Machine Intelligence-Synergy Systems of Chinese Academy of Sciences, Shenzhen 518055, China. chenwzwx@163.com.|Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. chenwzwx@163.com.|Shenzhen Key Laboratory of Electromagnetic Control, Shenzhen University, Shenzhen 518060, China. chenwzwx@163.com.
authors.forename: Wanzhen
authors.initials: W
authors.lastname: Chen
authors.affiliation: Key Laboratory of Human-Machine Intelligence-Synergy Systems of Chinese Academy of Sciences, Shenzhen 518055, China. wzhen8712@126.com.|Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. wzhen8712@126.com.|Nanshan Hospital of Guangdong Medical College, Shenzhen 518052, China. wzhen8712@126.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Shenzhen Yingda Strong Technology Co., Ltd, Shenzhen 518112, China. zhaisons@163.com.
authors.forename: Haiqing
authors.initials: H
authors.lastname: Zou
authors.affiliation: Key Laboratory of Human-Machine Intelligence-Synergy Systems of Chinese Academy of Sciences, Shenzhen 518055, China. l.a.krundel@lboro.ac.uk.|Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. l.a.krundel@lboro.ac.uk.|Electronic Systems Design Laboratory, School of Electronic, Electrical, and Systems Engineering, Loughborough University, Loughborough LE11 3TU, UK. l.a.krundel@lboro.ac.uk.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Krundel
authors.affiliation: Key Laboratory of Human-Machine Intelligence-Synergy Systems of Chinese Academy of Sciences, Shenzhen 518055, China. gl.li@siat.ac.cn.|Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. gl.li@siat.ac.cn.
authors.forename: Guanglin
authors.initials: G
authors.lastname: Li
mesh_terms: D000328:Adult; D058266:Dielectric Spectroscopy; D004553:Electric Conductivity; D004558:Electric Stimulation / Q000295:instrumentation*; D004566:Electrodes; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D008297:Male; D009469:Neuromuscular Junction / Q000502:physiology*; D013784:Textiles
keywords: electrode-electrolyte interface; finite element modeling; neuromuscular electrical stimulation; stimulating comfort; textile electrode