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Soft ionic-hydrogel electrodes for electroencephalography signal recording

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Abstract

Wet gel electrodes have been widely used for electroencephalography (EEG) signal recording, which generally causes skin abrasion and longer preparation time. In this paper, we present soft ionic-hydrogel based electrodes to overcome such drawbacks. In order to conveniently measure the EEG signals, we design the claw-like and patch-like structures for robust connection between metal (Ag/AgCl) electrodes and skin scalps. Next, we experimentally show that the soft ionic-hydrogel based electrodes have similar performance with the conventional wet gel electrodes in terms of the short-circuit noise, electrical impedance, and skin-electrode contact impedance on unprepared human skin, significantly better than dry electrodes and water-based electrodes. We further perform the EEG measurements and steady-state visual evoked potentials (SSVEP) experiments with five subjects to verify the effectiveness of the soft ionic-hydrogel based electrodes. The experimental results demonstrate that our developed soft ionic-hydrogel electrodes can record high-quality EEG signals in a fast and clean way, being a compelling option for EEG-based brain-computer interfaces.

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Authors and Affiliations

  1. Robotics Institute, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China

    XinJun Sheng, Zhun Qin, HaiPeng Xu, XiaoKang Shu, GuoYing Gu & XiangYang Zhu

  2. State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai, 200240, China

    XinJun Sheng, GuoYing Gu & XiangYang Zhu

Authors
  1. XinJun Sheng
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  2. Zhun Qin
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  3. HaiPeng Xu
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  4. XiaoKang Shu
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  5. GuoYing Gu
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  6. XiangYang Zhu
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Corresponding author

Correspondence to XinJun Sheng.

Additional information

This work was supported by the National Key R&D Program of China (Grant No. 2018YFB1307200), the National Natural Science Foundation of China (Grant Nos. 91948302, and 51905339), and the Science and Technology Commission of Shanghai Municipality (Grant No. 18JC1410400).

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Sheng, X., Qin, Z., Xu, H. et al. Soft ionic-hydrogel electrodes for electroencephalography signal recording. Sci. China Technol. Sci. 64, 273–282 (2021). https://doi.org/10.1007/s11431-020-1644-6

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  • DOI: https://doi.org/10.1007/s11431-020-1644-6

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