The brains of babies as young as four months respond to seeing another person’s hand being touched, researchers at Goldsmiths, University of London and the University of Essex have shown.
The new study suggests that even at this young age babies are able to vicariously experience the tactile sensations of others. Touch is our earliest sense and understanding its origins is particularly important as it is vital to the bond that forms between babies and parents.
A report of the research will be published in the journal Developmental Cognitive Neuroscience.
The researchers showed 15 four-month-old babies short video clips of a paintbrush either gently touching another person’s hand or touching the table surface next to the hand. At the same time as seeing these clips the babies felt a touch sensation generated by a vibrating ‘tactor’ device fitted inside scratch mittens.
A ‘cap’ of electrodes was placed on the babies’ heads. This was used to measure ‘peaks’ in electrical activity (somatosensory evoked potentials – ‘SEPs’) generated in the touch areas of the babies’ brains (somatosensory cortex) when the vibrating ‘tactor’ delivered a touch to their hands. The researchers found these SEPs were supressed when they simultaneously watched someone else’s hand being touched – suggesting that seeing someone else being touched influenced the babies’ perceptions of touch to their own hands.
Professor Andy Bremner, Head of Psychology at Goldsmiths and senior author, said: “We know that in adults seeing other people being touched, or touching objects, activates similar brain areas as when we experience touch ourselves. However, we have only just begun to study how this ‘vicarious mapping’ of experiences, something vital to feeling empathy, develops in early life.
“We found that in these young babies the prominent ‘peaks’ in activity in brain regions related to touch were significantly affected by watching someone else’s hand being touched. It suggests that, even at just four months, babies can, to some extent, vicariously ‘feel’ what’s happening to another person, and this might represent the early sensory origins of the empathic responses which we as adults have for others.”
Further research will help shed light on how specific this effect is. For instance, further questions concern how much like a human hand the seen hand has to be for young babies to show this ‘vicarious mapping’ of experience.
A report of the research, entitled ‘Cortical signatures of vicarious tactile experience in four-month-old infants’, will be published in the journal Developmental Cognitive Neuroscience.