Vicarious somatosensory activations contribute to prosocial decision-making, new work led by investigators from the Netherlands Institute for Neuroscience suggests.
Previous neuroscience studies have shown that when we see somebody in pain our brain activates tactile and emotional regions as if we ourselves were in pain. This study from Selene Gallo (Netherlands Institute for Neuroscience, KNAW) asked whether altering activity in these tactile brain regions while witnessing the pain of others would alter people’s willingness to help.
The results are of great importance to understand our social human nature and to find treatments for pathologies, like psychopathic individuals.
Reducing Others Pain
Researchers from the Social Brain Lab, led by KNAW’s Valeria Gazzola and Christian Keysers, gave participants the opportunity to reduce the pain of a victim receiving a swat on her hand. They could reduce the pain by giving up money they could have otherwise taken home while their tactile brain activity was measured and altered.
The researchers used electroencephalography, a method to record electrical activity of the brain, in healthy human participants. With this method, they found that the activity in tactile cortices increased when participants increased their donation.
Later they altered brain activity by using neuromodulation. Normally participants gave more money when the victim experienced more pain.
But when interfering with tactile activity two related phenomena were observed: (a) people became less able to perceive in how much pain the other person was and (b) they no longer adapted their donations as appropriately to the needs of the other.
Tactile Cortices Social Function
The results suggest that our tactile cortices, primarily evolved to perceive touch and pain on our body, have an important social function.
They contribute to prosocial decision-making by helping to transform the sight of bodily harm into an accurate feeling for how much pain the victim experiences. This feeling is necessary to adapt our helping to the needs of others.
Providing a link between empathy for pain and prosocial behavior at the neural level is crucial to understand our social human nature and target pharmacological approaches to treat pathologies in which these mechanisms dysfunction, for example in psychopath individual or in children with callous unemotional traits.
The Gazzola lab is funded by the Dutch Science Foundation’s Innovational Research Incentives Scheme (VIDI), the Brain & Behavior Research Foundation, the European Commission’s Marie Skłodowska-Curie actions, and the Consejo Nacional de Ciencia y Tecnología of Mexico.
Selene Gallo, Riccardo Paracampo, Laura Müller-Pinzler, Mario Carlo Severo, Laila Blömer, Carolina Fernandes-Henriques, Anna Henschel, Balint Kalista Lammes, Tatjana Maskaljunas, Judith Suttrup, Alessio Avenanti, Christian Keysers, Valeria Gazzola The causal role of the somatosensory cortex in prosocial behaviour eLife 2018;7:e32740 DOI: 10.7554/eLife.32740