Cognitive and neural mechanisms involved in interactions between touch and emotion

Touch has been described as the most fundamental means of contact with the world and the most primitive modality among all sensory systems. In the past, the study of emotional communication has focused almost exclusively on facial and vocal channels but has ignored the channel for the sense of touch. However, the latest studies have documented that the sense of touch can convey at least six emotions, and its accuracy rate is comparable to that of facial expressions and vocal communication. Moreover, there is also mounting evidence indicating that the modality of touch encompasses two dimensions, which provide not only its well-recognized discriminative input from glabrous skin to sensory cortex but also an affective input from hairy skin to the insular cortex because a type of low-threshold mechanosensitive receptor that innervates hairy skin has been shown to convey emotions via C fibers. In light of recent advances in our research, this chapter aims to illustrate the cognitive and neural mechanisms that underlie interactions between touch and emotion.