Department of Electrical and Electronic Engineering, University of Cagliari, Cagliari, Italy.
Center for Bionics and Pain Research, Mölndal, Sweden.
Sci Rep. 2023 Jan 28;13(1):1588. doi: 10.1038/s41598-023-28594-0.
Electrical stimulation of the nerves is known to elicit distinct sensations perceived in distal parts of the body. The stimulation is typically modulated in current with charge-balanced rectangular shapes that, although easily generated by stimulators available on the market, are not able to cover the entire range of somatosensory experiences from daily life. In this regard, we have investigated the effect of electrical neurostimulation with four non-rectangular waveforms in an experiment involving 11 healthy able-bodied subjects. Weiss curves were estimated and rheobase and chronaxie values were obtained showing increases in stimulation time required to elicit sensations for some waveforms. The localization of the sensations reported in the hand also appeared to differ between waveforms, although the total area did not vary significantly. Finally, the possibility of distinguishing different charge- and amplitude-matched stimuli was demonstrated through a two-alternative-forced-choice (2AFC) match-to-sample task, showing the ability of participants to successfully distinguish between waveforms with similar electrical characteristics but different shapes and charge transfer rates. This study provides evidence that, by using different waveforms to stimulate nerves, it is possible to affect not only the required charge to elicit sensations but also the sensation quality and its localization.
电刺激神经会引起身体远端明显的感觉。刺激通常以平衡电荷的矩形电流来调制，虽然这种电流很容易被市场上的刺激器产生，但它无法涵盖日常生活中所有的感觉体验。在这方面，我们在一项涉及 11 名健康的健全受试者的实验中，研究了四种非矩形波形的电神经刺激的效果。我们估计了魏斯曲线，获得了阈值和弛豫时间值，结果表明，一些波形需要更长的刺激时间才能引起感觉。报告的手部感觉的定位似乎也因波形而异，尽管总面积没有显著变化。最后，通过二选一强制选择（2AFC）匹配样本任务，证明了区分不同电荷和幅度匹配刺激的可能性，表明参与者能够成功区分具有相似电学特性但形状和电荷传递率不同的波形。这项研究提供了证据表明，通过使用不同的波形来刺激神经，不仅可以影响引起感觉所需的电荷量，还可以影响感觉质量及其定位。
