Yawning is contagious in humans. 'Catching' yawns happens with many other social mammals including chimpanzees and dogs. However, researchers from Texas-based Baylor University have revealed that selfish and manipulative people will not respond to yawning after spotting someone else yawn. During the study it was observed that people with psychopathic characteristics, those with anti-social lifestyle and lacking in empathy, are less likely to be affected by 'contagious yawning' than those who are empathetic.
The researchers said, "Yawning after spotting someone else yawn is associated with empathy and bonding." Lead researcher Brian Rundle, doctoral student in psychology and neuroscience, said, "You may yawn even if you do not have to. We all know it and always wonder why. I thought, 'If it's true that yawning is related to empathy, I'll bet that psychopaths yawn a lot less'. So I put it to the test."
For the study, 135 college students were shown 10-second video clips of different facial movements- a yawn, a laugh or a neutral face. Based on the psychological test results and the frequency of yawns, the study suggested that the less empathy a person had, the less likely he or she was to 'catch' a yawn.
Rundle said, "The take-home lesson is not that if you yawn and someone else does not, the other person is a psychopath. There is a neurological connection between psychopathy and contagious yawning and this is a good starting point to ask more questions."
The study appeared online in Personality and Individual Differences.