The team, at UCL's Wellcome Department of Imaging Neuroscience, set out to find out what happens to our brains when we empathise with the feelings of others, how the brain understands how something feels for another human, and whether such empathetic responses are triggered rather automatically by the mere perception of someone else being in pain.
The UCL team investigated pain-related empathy in 16 couples, under an assumption that couples are likely to feel empathy for each other. Brain activity in the woman was assessed while painful stimulation was applied to her or to her partner's right hand through an electrode attached to the back of the hand. Both hands were placed on a tilted board allowing the subject, with help of a mirror system, to see both hands. Behind this board was a large screen upon which flashes of different colours were presented. The colours indicated whether to expect painful or non painful stimulation. This procedure enabled to measure pain-related brain activation when pain was applied to the scanned subject (the 'pain matrix') as well as to her partner (empathy for pain).
The team found that not the entire 'pain matrix' was activated when empathizing with the pain of others. Some sensory regions of your brain code for the location and the objective intensity of the painful stimulus, while other brain regions process how unpleasant you subjectively felt the pain to be. For instance, someone involved in a car accident will hardly feel pain even if they are severly injured, while if you expect to be infected by a contagious desease, every slight scratch will feel like a burning pain.
The researchers observed that empathy for pain involved the context-dependent affective aspects of pain but not the sensory-discriminative aspects of pain. It involves the same brain regions found to be involved when you anticipate getting pain. You get aroused and emotional but you do not feel the actual pain on your hand.
"The results suggest that we use emotional representations reflecting our own subjective feeling states to understand the feelings of others. Probably, our ability to empathize has evolved from a system for representing our own internal bodily states", says author Dr Tania Singer.
"The significance of this research is that, for the first time, brain imagers were able to study empathic processes 'in vivo' in the usually unnatural scanning environment and show that emotional and not cognitive processess are triggered by the mere perception of a symbol indicating that your loved-one is in pain.
"Our human capacity to 'tune in' to others when exposed to their feelings may explain why we do not always behave selfishly in human interactions but instead engage in altruistic, helping behaviour, suggests Dr Tania Singer.
Notes for Editors
1. "Empathy for pain involves the affective but not sensory components of pain," is published in the 20 February edition of Science.
2. All media enquiries should be addressed to Dominique Fourniol in the UCL Media Relations Office on 207-679-9728.