Chaichanasittikarn Oranatt, Diaz Lauren, Thomas Neha, Candrea Daniel, Luo Shiyu, Nathan Kevin, Tenore Francesco V, Fifer Matthew S, Crone Nathan E, Christie Breanne, Osborn Luke E
Department of Biomedical Engineering, Case Western Reserve University.
Human Fusions Institute, Case Western Reserve University.
medRxiv. 2025 Jul 11:2025.07.09.25331186. doi: 10.1101/2025.07.09.25331186.
Haptic feedback can play a useful role in rehabilitation and brain-computer interface applications by providing users with information about their system or performance. One challenge delivering tactile stimulation is not knowing how the haptic sensation is actually perceived, irrespective of the stimulation amplitude, during real-world use and beyond controlled psychophysical experiments. In a participant with chronically implanted electrocorticography arrays, we observed that perceived intensity of haptic vibration on the fingertips was represented in the high-gamma (HG) frequency band (70-170 Hz) in the somatosensory cortex. The five fingers of the participant's right hand were represented by distinct channels in the implanted array and modulated by the vibration amplitude at the fingertips. Although it reliably varied with the vibration amplitude, we found that HG activity had a stronger relationship with the actual perceived intensity of haptic stimulation ( = 0.45, < 10 ). These results demonstrate that neural signals, specifically HG activity, in the somatosensory cortex can represent qualities of perceived haptic intensity regardless of the stimulation amplitude, which could enable a new way to passively quantify or ensure effective haptic feedback to a user.
触觉反馈通过向用户提供有关其系统或性能的信息，可在康复和脑机接口应用中发挥有益作用。在实际使用中以及超出受控心理物理学实验范围时，传递触觉刺激面临的一个挑战是，无论刺激幅度如何，都不清楚触觉感受实际上是如何被感知的。在一名长期植入皮层脑电图阵列的受试者中，我们观察到，指尖触觉振动的感知强度在体感皮层的高伽马（HG）频段（70 - 170赫兹）中得到体现。受试者右手的五根手指在植入阵列中由不同的通道表示，并由指尖的振动幅度调制。尽管它随振动幅度可靠地变化，但我们发现HG活动与触觉刺激的实际感知强度有更强的关系（ = 0.45，< 10 ）。这些结果表明，体感皮层中的神经信号，特别是HG活动，无论刺激幅度如何，都可以表示感知到的触觉强度的特征，这可能为被动量化或确保向用户提供有效的触觉反馈开辟一条新途径。
