TECNALIA, Basque Research and Technology Alliance (BRTA), Derio, Spain.
TECNALIA, Basque Research and Technology Alliance (BRTA), Donostia-San Sebastián, Spain.
Artif Organs. 2023 Jan;47(1):117-128. doi: 10.1111/aor.14400. Epub 2022 Sep 20.
Current Perception Threshold (CPT) is a technique used for diagnostic purposes that applies sinusoidal currents transcutaneously at 5 Hz, 250 Hz, and 2KHz to preferentially excite C, Aδ, and Aβ afferent nerve fibers correspondingly. This fact may be interesting for evoking different electrotactile sensations for a wide variety of applications.
Sensations evoked by 5 Hz, 250 Hz, and 2KHz frequencies; sinusoidal, square, and 250 μs-pulsed waveforms; and conventional and concentric electrode configurations were analyzed in 19 healthy volunteers. Stimuli were applied in the dorsum of the hand in a double-blind manner and CPTs were defined based on participants' verbal feedback. After each stimulus participants filled in a form with sensation modality, irradiation, intensity, and emotion descriptors.
The frequency showed a significant effect on the four domains of evoked sensations and the waveform showed a significant effect on the modality domain. For most waveform and electrode configuration combinations, 5 Hz evoked mostly a low-intensity prickling sensation; 250 Hz mostly evoked an uncomfortable medium-intensity tingling sensation; and 2KHz mostly evoked a low-intensity tingling sensation. No thermal or noxious sensations were evoked. A significant interaction effect was only found between the frequency and the waveform factors. The electrode configuration did not show either a significant effect on the evoked sensations or an interaction effect with the frequency or waveform type.
Transcutaneous electrical stimulation may evoke different sensations at different frequencies due to the preferential activation of different fiber types. The results of these analysis could be used to enhance human-machine/computer-interaction systems based on electrotactile feedback.
当前感知阈值（CPT）是一种用于诊断目的的技术，它以 5 Hz、250 Hz 和 2 KHz 的频率经皮应用正弦电流，以相应地优先兴奋 C、Aδ 和 Aβ传入神经纤维。这一事实可能对于激发各种应用的不同触觉有意义。
分析了 19 名健康志愿者对 5 Hz、250 Hz 和 2 KHz 频率、正弦波、方波和 250 μs 脉冲波以及传统和同心电极配置引起的感觉。以双盲的方式在手背施加刺激，并根据参与者的口头反馈定义 CPT。每次刺激后，参与者填写一份感觉方式、辐射、强度和情绪描述的表格。
频率对诱发感觉的四个域有显著影响，而波形对方式域有显著影响。对于大多数波形和电极配置组合，5 Hz 主要引起低强度刺痛感；250 Hz 主要引起不适的中等强度刺痛感；2 KHz 主要引起低强度刺痛感。没有诱发热觉或痛觉。只有频率和波形因素之间存在显著的相互作用效应。电极配置对诱发感觉没有显著影响，也没有与频率或波形类型的相互作用效应。
由于不同纤维类型的优先激活，经皮电刺激可能在不同频率下引起不同的感觉。这些分析的结果可用于增强基于触觉反馈的人机/计算机交互系统。
