loading page

Affective Touch is encoded by pupil dilation as a comprehensive social phenomenon
  • +3
  • Greta Bonino,
  • Alessandro Mazza,
  • Francesca Capiotto,
  • Annamaria Berti,
  • Lorenzo Pia,
  • Olga Dal Monte
Greta Bonino
University of Turin
Author Profile
Alessandro Mazza
University of Turin
Author Profile
Francesca Capiotto
University of Turin
Author Profile
Annamaria Berti
University of Turin
Author Profile
Lorenzo Pia
University of Turin
Author Profile
Olga Dal Monte
University of Turin

Corresponding Author:olga.dalmonte@unito.it

Author Profile

Abstract

Affective Touch plays a pivotal role in regulating emotions, fostering social bonds and nurturing affiliations with others. The emotional and arousing dimensions associated to Affective Touch are linked to the activation of the CT- fibres system, an afferent pathway attuned to those specific features of tactile stimulations which characterize gentle human caresses, such as touch velocity and the nature of the stroking source. While previous research has examined the physiological responses in relation to these individual features of Affective Touch, no study has explored how they interact to shape autonomic activity. In this study, we investigated whether and how touch velocity (CT-optimal vs. CT-suboptimal) and the nature of the touching effector (Human hand vs. Artificial hand) influenced the participants’ pupil dilation and their subjective experience during tactile stimulation. We observed a higher pupil dilation when touch was delivered simultaneously at CT-optimal speed and by a human hand. This kind of touch invoked a supralinear enhancement of pupil dilation indicating that the combination of these two features induced a significantly stronger autonomic activation than the summed effects of each delivered separately. Moreover, this specific type of touch was perceived as the most pleasant compared to all other tactile stimulations. Therefore, pupil dilation appears to map the positive and pleasant experience of human-to-human tactile interactions. Collectively, our results support the notion that the autonomic nervous system encodes the emotional and hedonic aspects associated with Affective Touch as a complex and holistic social experience, rather than solely responding to its low-level sensory properties.
06 Oct 2023Submitted to Psychophysiology
09 Oct 2023Submission Checks Completed
09 Oct 2023Assigned to Editor
09 Oct 2023Review(s) Completed, Editorial Evaluation Pending
11 Nov 2023Reviewer(s) Assigned