Anecdotal evidence and clinical trials have demonstrated positive benefits of massage for infants. A recent study published in Psychological Science, a journal of the Association for Psychological Science, further supports those results. The study found that infants show unique physiological and behavioral responses to pleasant touch, potentially helping to strengthen the bonds between child and parent and promote early social and physiological development.

Previous studies with adults have shown that stroking the skin with a particular velocity activates a specific type of touch receptor, leading to the sensation of “pleasant” touch. Cognitive neuroscientists Merle Fairhurst and Tobias Grossmann of the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany, hypothesized that this type of response might emerge as early as infancy.

For the study, infants sat on their parents’ laps while an experimenter used a paintbrush to stroke the back of the babies’ arms with three defined velocities: 0.3, 3, or 30 cm per second. The results showed that the infants’ heart rates slowed, but only in response to medium velocity brushstrokes. Interestingly, the infants’ heart rates correlated with the primary caregiver’s self-reported sensitivity to touch, e.g., the more sensitive the caregiver was to touch, the more the infant’s heart rate slowed.

The researchers propose that the infant’s sensitivity to pleasant touch stems from direct or vicarious experience of their caregiver’s sensitivity to social touch. Fairhurst adds, “Another possibility is that social touch is genetically heritable and therefore correlated between caregivers and infants.”

According to the researchers, the findings “support the notion that pleasant touch plays a vital role in human social interactions by demonstrating that the sensitivity to pleasant touch emerges early in human development.” The ability to perceive and sensitively respond to pleasant touch is essential early in life because of the fundamental role that touch plays in affiliation, bonding and synchrony between infants and caregivers.

“With regards to massage therapy, our research was very much based on a growing literature supporting the functional role touch has in health. The pleasant touch fibres we believe are responsible for our results are present in adults and are possibly stimulated by therapeutic touch, though it should be noted that these fibres are not pressure sensors, but instead are stimulated by a certain velocity of stroking. If their therapeutic manipulation activated these fibres, it is possible that it might have physiological consequences,” Fairhurst explains. “In our paper and those of our co-authors before us, we have identified that this subclass of sensory fibres is selectively activated by a certain, moderate velocity stroke (3 m/s). In infants and adults, this type of stroking results in physiological and behavioural changes not seen at high and very slow velocity stroking.”

Fairhurst clarifies that this study does not deal with massage per se. However, if the interaction between parent and child included stroking at a moderate velocity, it might activate these sensory receptors and result in decreased heart rate and greater attention towards the stimulation, she asserts.