To sync or not to sync : neural synchronisation and perception of emotional pain in human hand-holding behaviour

Abstract

Tactile touch is paramount throughout one’s lifespan and serves various important functions such as the buffering of stress, provision of comfort, and an analgesic effect on physical pain. Specifically, studies have shown that the analgesic effect could have been brought upon by a mechanism of neural synchrony between the two partners. The main aim of the present study was to investigate further into the effect of neural synchrony and hand-holding behaviour among couples on emotional pain, instead of physical ones. The study employed a hyper-scanning paradigm using the functional near infra-red spectroscopy (fNIRS) and participants viewed image stimuli that are either negative (to elicit emotional pain) or neutral, while alone, holding hands, or not holding hands. It was found that while the act of hand-holding behaviour did not significantly alleviate emotional pain, there was indeed a mechanism of neural synchrony across all the conditions, especially when modulated by relationship duration and relationship satisfaction. These significances were observed in the frontal regions of the pre-frontal cortex and the functions of the specific structures were discussed in the paper. More importantly, the current study highlighted the controversial results of disadvantageous synchrony when the couples are both in high negative affect, and the protective role hand-holding behaviour can play in this process. In all, the findings could add to current literature on the effect and neural correlates of hand-holding behaviour that could possibly inform various populations such as therapists (e.g. family and couple therapy) and physicians, on best practises when utilizing tactile touch.