Researchers say psychopaths are immune to yawning waves

If you've been suspicious that this kind of weird colleague is actually a heartless psychopath, you can now take a test: start yawning next to the person and see if they'll be infected and yawn too. If it does not, there is a possibility that you may be next to a true psychopath.

Yawning waves are quite common among people. Just start the gesture for those around you to start yawning too, and it doesn't necessarily have to do with sleep. Researchers believe that this contagious wave has to do with a primitive form of communication and connection between humans - and it can also exist between other species, even between you and your pet dog.

Now, new studies reveal yet another aspect of this phenomenon, claiming that psychopaths are immune to this type of contagion. The research was conducted at the University of Baylor, Texas, United States.

135 people were analyzed in a test called Psychopathic Personality Inventory, which can detect traces of cruelty, selfishness, impulsiveness, aggression and empathy. In a dimly lit room, volunteers were exposed to a series of videos that sought to bring about an emotional reaction, with people smiling, laughing or yawning.

In the end, those who scored low on this analysis were twice as likely to yawn, unlike those who showed more aspects of a psychopath in their personality. That is, the less empathy the person showed, the less chance of yawning as well.

At this point, it's good to note that not every individual unable to yawn with you is likely to become a serial killer. A psychopath is someone who suffers from a lack of social emotions, who cannot identify with what the other is feeling. Studies conducted in the past have shown that autistic children are not infected and yawned either.

According to chief researcher Brian Rundle, many of the analysts didn't yawn either because they didn't identify with the stranger on the screen. A 2011 study from the University of Pisa states that the yawning wave is more contagious if the people involved have a close relationship.

For a better analysis of the data, especially with regard to empathy, Rundle states that further research with an even larger number of volunteers should be conducted soon.