Decoding social touch: A multi-modal exploration of tactile perception, gender and culture

Social touch plays a vital role in human development, communication, and general well-being. However, the mechanisms underlying how social touch elicits pleasant or aversive responses are poorly understood. Furthermore, it remains unclear how alterations in sensory processing, at both the perceptual level (i.e. detection and discrimination of stimuli) and behavioral level (i.e. response to stimuli), shape the experience of social touch, in addition to contextual factors such as gender and culture. In the current study, we used vibrotactile psychophysics and a novel social touch paradigm to assess the association between tactile perceptual differences and social touch preference in two cross-cultural cohorts (56 adults in the UK and 21 adults in Singapore). We found that participants with poorer tactile discrimination thresholds in both cohorts had lower pleasantness ratings for social touch, and higher pleasantness ratings for non-social touch, with a stronger predictive effect than gender or culture alone. We also found evidence of strong gender effects, such that female participants rated different-gender touch as less pleasant than males. Singaporean participants also showed lower preferences for social touch than UK participants. Our results suggest a bottom-up perceptual mechanism in linking poorer tactile discrimination with greater social touch aversion in adults. Furthermore, while some cultural differences between cohorts were observed at the contextual level, perceptual contributions to social touch preference appeared to be conserved, suggesting a shared biological mechanism between cultures. These findings could have implications for clinical conditions that are characterised by altered sensory and social processing.