Animals also express empathy through comforting
Research in prairie voles conducted bij Prof. Frans de Waal and his American colleagues has provided strong indications that consolation behaviour is a basic, congenital empathic mechanism. They have also proven that the ‘cuddle hormone’ oxytocin plays a vital role in consolation. Their results suggest that prairie voles and humans recognise stress in others via the same brain mechanism. The results of the study, which will be published in Science on January 21st, are therefore of interest for research into a number of psychiatric disorders.
Humans are not the only animals to console fellow members of their species: Prof. Frans de Waal discovered the behaviour in chimpanzees at Burgers’ Zoo in 1979. Since then, biologists have debated whether consolation behaviour is the result of empathy or is a conditioned social behaviour.
Consolation is bodily contact in order to reduce the stress or fear experienced by another individual. Humans and chimpanzees console one another by embracing and kissing, but other animals such as elephants and dogs also display forms of consolation. De Waal and his American colleagues have proven for the first time that rodents are also capable of consolation behaviour. This alone is evidence for the hypothesis that empathy is widespread. Prof. De Waal has always been convinced that this is the case, and argued against overly cognitive interpretations of empathy.
Finding a rodent model for empathy is a promising development for the future of research into the connection between autistic behaviour and the role of oxytocin in the brain.
But the strongest evidence that the behaviour is the result of empathy is that the researchers have observed similarities between the brain mechanisms for empathic behaviour in humans and consolation in animals. “Scientists have always been hesitant to ascribe empathy to animals. They assume that animals only do things for other individuals in their own self-interest. However, that explanation never worked very well for consolation behaviour. This is why this research is so important”, according to Prof. Frans de Waal, behavioural biologist at Utrecht University and Emory University in Atlanta, USA. He conducted his research in cooperation with colleagues from Emory University, including Prof. Lawrence Young, who is world renowned for his research into the neuroscience of social behaviour.
In the study, a female prairie vole was removed from her male partner and exposed to a stressful situation. When reunited with his partner, the male seemed to be as affected as the female by the experience. Although he had been safe in his cage, the researchers measured an increase in the male’s stress hormone corticosterone. Humans experience similar emotional contagion. The male consoled his female partner by grooming her intensively.
However, the consoling behaviour did not occur when the oxytocin receptors in the anterior cingulate cortex of the male’s brain were blocked. Oxytocin is closely related to empathy and the formation of social bonds in humans. Male and female prairie voles form pair bonds for life, and therefore have strong social bonds.
In several psychiatric disorders, such as autism and schizophrenia, the person’s ability to recognise and react to other people’s emotions is disrupted. Finding a rodent model for empathy is a promising development for the future of research into the connection between autistic behaviour and the role of oxytocin in the brain, according to Prof. Frans de Waal.
This research was funded in part by the American National Institute of Mental Health, the Office of Research Infrastructure Programs/OD P51OD011132, and the Silvio O. Conte Center for Oxytocin and Social Cognition.
Oxytocin-Dependent Consolation Behavior in Rodents
J.P. Burkett, E. Andari, Z.V. Johnson, D.C. Curry, F.B.M. de Waal*, & L.J. YoungScience, January 21st 2016