Humans can experience emotional contagion—that is, if you interact with somebody who is experiencing negative emotions, you may start to feel down yourself. Researchers from Austria recently tested whether ravens, known to be social and intelligent birds, could experience a similar phenomena.
Eight pairs of ravens were formed, where each bird was partnered with another bird it knew well. One bird from each pair was picked as a demonstrator and was shown some tasty dog kibble as well as some less desirable carrots. The researchers then induced either a positive or negative emotional state in the demonstrator by taking away the carrots (leaving behind the tasty reward) or the dog kibble, respectively. The partner could see the demonstrator’s behavior, but not the food. Both the demonstrator and its partner were then offered a third box. If the birds were quick to investigate this new box, hoping for a tasty snack, that was interpreted as optimism. If they were more interested in their environment outside the new box, researchers assumed they were feeling pessimistic about the odds of good food being inside.
The demonstrators generally were more pessimistic when they had been denied their preferred food and more optimistic when the less desirable sustenance had been taken away. Their partners mirrored their demonstrator’s pessimism, but did not mirror the demonstrator’s behavior when the demonstrator was feeling more optimistic. Thus, ravens may experience emotional contagion in the form of spreading negative emotions from one bird to another. The researchers hypothesize the observing birds might have not shared their demonstrator’s excitement because they had not been able to themselves access the food that the demonstrator was excited about.
The authors suggest that the existence of emotional contagion in both ravens and distantly related animals, including primates, might be caused by convergent evolution. This means the trait could have evolved independently separate times in different species. Alternatively, the parts of the brain that make emotional contagion possible may be the same in both ravens and mammals. Investigating these questions were beyond the scope of this study, but may be interesting for future research.
Jessie E.C. Adriaense is a PhD student at the University of Vienna who studies animal cognition and has several papers on animal empathy and emotional contagion.
Managing Correspondent: Emily Kerr
Scientific Article: Negative emotional contagion and cognitive bias in common ravens (Corvus corax)
Popular Press Article: Researchers find evidence of negative emotional contagion in lab ravens
Image Credit: Marcin Klapczynski