Development of a Polymer-Based MEG-Compatible Vibrotactile Stimulator for Studying Neuromagnetic Somatosensory Responses

Min-Young Kim,Sang-Youn Kim,Tae-Heon Yang,Won-Hyeong Park,Seong-Min Hwang,Hyukchan Kwon,Kiwoong Kim

doi:10.1109/access.2019.2961122

Abstract

Vibrotactile technology has been gaining increasing interest for effective human-computer communication in various applications. In addition to psychophysical approaches commonly used to study tactile vibrations, neurocognitive responses to vibrotactile stimuli can provide new insights into mechanisms underlying human vibrotactile perception. In this study, we developed a magnetoencephalography (MEG)-compatible vibrotactile stimulation device based on a polyvinyl chloride (PVC) gel actuator to study neuromagnetic somatosensory responses. A symmetric, double-layered PVC gel structure was applied to minimize the magnetic noise from the actuator. The device was used to generate sinusoidal stimuli at high frequencies to activate mechanoreceptors responsible for high-frequency vibrations greater than 50 Hz, and this device showed very little variability in stimulation onset time from the displacement measurements. We successfully observed vibrotactile-evoked magnetic fields by analyzing whole-head MEG data recorded during the high-frequency vibrotactile stimulation of the fingertips. Prominent peak responses were observed at approximately 56 ms (M50) in the contralateral hemisphere and at approximately 100 ms (M100) in both hemispheres. We identified the activation of contralateral primary somatosensory areas as a source of the vibrotactile M50 response. These results demonstrate the feasibility of using our new device to study vibrotactile perception with neuromagnetic imaging methods.

Highlights

The widespread use of touchscreen technology in the mobile industry was accelerated by the development of smartphones and tablet computers, replacing traditionally used mechanical keypads with capacitive touch sensors for an interactive display environment
To provide functional neuroimaging insights into vibrotactile perception studies, we developed an MEG-compatible vibrotactile stimulation device based on a polyvinyl chloride (PVC) gel actuator
In the present work, we developed an MEG-compatible vibrotactile stimulation device based on a PVC gel actuator to study vibrotactile perception using neuromagnetic imaging methods

Summary

Introduction

The widespread use of touchscreen technology in the mobile industry was accelerated by the development of smartphones and tablet computers, replacing traditionally used mechanical keypads with capacitive touch sensors for an interactive display environment. The associate editor coordinating the review of this manuscript and approving it for publication was Ran Su. display and intuitive user interfaces for simple operations, the flat physical surface of touchscreens lacks tactile feedback, thereby increasing the user’s attentional demands to control touchscreen interaction [1]. Adding tactile feedback to touchscreen mobile devices has shown great potential for improving the user performance of touchscreen interactions; tactile interface systems have gained attention as effective channels for communication between users and interaction devices [1]–[3]. The psychophysical and neurophysiological analyses of tactile vibrations have provided the fundamental framework for understanding human vibrotactile perception and the guidelines to design optimized vibrotactile devices for potential applications [8]–[12]

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Discussion

Conclusion