The human "feel" of touch contributes to its perceived pleasantness

This study explored whether a human-like feel of touch biases perceived pleasantness and whether such a bias depends on top-down cognitive and/or bottom-up sensory processes. In 2 experiments, 11 materials were stroked across the forearm at different velocities (bottom-up) and participants rated tactile pleasantness and humanness. Additionally, in Experiment 1, participants identified the materials (top-down), whereas in Experiment 2, they rated each material with respect to its somatosensory properties (bottom-up). Stroking felt most pleasant at velocities optimal for the stimulation of CT-afferents, a mechanosensory nerve hypothesized to underpin affective touch. A corresponding effect on perceived humanness was significant in Experiment 1 and marginal in Experiment 2. Whereas material identification was unrelated to both pleasantness and humanness, we observed a robust relation with the somatosensory properties. Materials perceived as smooth, slippery, and soft were also pleasant. A corresponding effect on perceived humanness was significant for the first somatosensory property only. Humanness positively predicted pleasantness and neither top-down nor bottom-up factors altered this relationship. Thus, perceiving gentle touch as human appears to promote pleasure possibly because this serves to reinforce interpersonal contact as a means for creating and maintaining social bonds. (PsycINFO Database Record (c) 2020 APA, all rights reserved).