Investigation of Adhesive Perception Based on Friction and Brain Activation

The enhancement of adhesive perception is crucial to maintaining a stable and comfortable grip of the skin-touch products. To study the tactile perception of adhesive surfaces, subjective evaluation, skin friction and vibrations, and neurophysiological response of the brain activity were investigated systematically. Silicone materials, which are commonly used for bionic materials and skin-touch products, were chosen for the tactile stimulus. The results showed that with the increasing of surface adhesion, the dominant friction transferred from a combination of adhesive friction and deformation friction to adhesive friction. The friction coefficient and vibration amplitude had strong correlations with the perceived adhesion of surfaces. The parietal lobe and occipital lobe were involved in adhesive perceptions, and the area and intensity of brain activation increased with the increasing surface adhesion. Surfaces with larger adhesion tended to excite a high P300 amplitude and short latency, indicating that the judgment was faster and that more attentional resources were involved in adhesive perception. Furthermore, the electroencephalograph signals of the adhesive perception were simulated by the neural mass model. It demonstrated that the excitability and intensity of brain activity, and the connectivity strength between two neural masses increased with the increasing surface adhesion. This study is meaningful to understand the role of surface adhesion in tactile friction and the cognitive mechanism in adhesive perception to improve the tactile experience of adhesive materials.