Infants Relax in Response to Pleasant Touches

The way infants respond to pleasant touches may strengthen the bond between parents and children and promote social and psychological development, according to a new study. Merie Fairhurst, cognitive neuroscientist, and her colleagues at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig Germany investigated how infants respond to pleasant touches after conducting research into adults’ physiological responses to a certain stroking velocity. The researchers discovered that infants were most relaxed and engaged by a moderate stroking speed.

For the study, the infants sat in their parents’ laps. An experimenter armed with a paintbrush stroked the back of the infants’ arms at slow, medium, or fast velocities (0.3, 3, or 30 centimeters per second, respectively). The researchers monitored the infants’ responses using physiological and behavioral measurements.

The results indicate that infants responded the most to the medium velocity stroking (3 centimeters per second). In response to medium velocity brush strokes, the infants’ physiological arousal, measured by their heart rates, decreased. The infants also exhibited higher levels of engagement with the medium velocity brush strokes, which was measured by the frequency and length of the infants’ glances at the source of the stroking

They also found that the parent or caregivers’ self-reported sensitivity to pleasant touches was correlated to the infants’ responses. That is, the more sensitive the parent was to such touches, the more the infant’s heart rate slowed in response to similar sensations.

These findings are important because perceiving and responding to touch is critical for developing infants. Touching plays a role in affiliation, bonding, and synchrony between infants and their caregivers. The results “support the notion that pleasant touch plays a vital role in human social interactions bu demonstrating that the sensitivity to pleasant touch emerges early in human development,” state the researchers.

This research is published in the journal Psychological Science.

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