title: Responses of cutaneous mechanoreceptors within fingerpad to stimulus information for tactile softness sensation of materials.
abstract: Softness sensation is one of primitive tactile textures. While the psychophysical characteristics of softness sensation have been thoroughly studied, it is lack of a deep understanding of the underlying neuromechanical principles. On the stimulus-response processes of human fingerpad touching fabrics and the physiological properties of slowly adapting type I (SAIs) cutaneous mechanoreceptors within fingerpad, a fabric-skin-receptor coupling model was built and validated. By the fabric-skin-receptor model a series of numerical experiments was conducted, and how the evoked neural responses of cutaneous mechanoreceptors change with the composite compliance of both fingerpad skin and the materials in contact was investigated. The results indicated that the evoked neural responses of populations of cutaneous mechanoreceptors by the physical stimulus from fabrics were nearly proportional to the perceived softness magnitude, and nonlinearly increased and then decreased with the effective elastic modulus of fabrics or the relative elastic modulus of fabrics to soft tissues within fingerpad, where the nonlinear inflection point depended on the touching force level. Therefore, it concluded that the tactile judgment of the physical information for softness sensation of objects was an encoding of neural responses of populations of SAIs cutaneous mechanoreceptors, and the physical information depended on the mechanical interaction of fingerpad and objects in contact.
authors.affiliation: Key Lab of Textile Science and Technology, Ministry of Education, Donghua University, Shanghai, 201620 People's Republic of China ; College of Textiles, Donghua University, Shanghai, 201620 China.
authors.forename: Jiyong
authors.initials: J
authors.lastname: Hu
authors.affiliation: Key Lab of Textile Science and Technology, Ministry of Education, Donghua University, Shanghai, 201620 People's Republic of China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Key Lab of Textile Science and Technology, Ministry of Education, Donghua University, Shanghai, 201620 People's Republic of China.
authors.forename: Ruitao
authors.initials: R
authors.lastname: Jiang
authors.affiliation: Institute for Brain Information Processing and Cognitive Neurodynamics, East China University of Science and Technology, Shanghai, 200237 People's Republic of China.
authors.forename: Rubin
authors.initials: R
authors.lastname: Wang
authors.affiliation: Key Lab of Textile Science and Technology, Ministry of Education, Donghua University, Shanghai, 201620 People's Republic of China ; College of Textiles, Donghua University, Shanghai, 201620 China.
authors.forename: Xin
authors.initials: X
authors.lastname: Ding
keywords: Elastic modulus; Mechanoreceptors; Neuromechanics; Softness; Tactile