An Italian study has found that individuals are more likely to catch on to the contagious effect of yawning in response to a close relative than they are to a friend or an acquaintance.
The action of yawning has long since been known to stimulate blood flow around the brain, a response which is now thought to be a natural way of maintaining alertness within a group situation.
The study in question found that the contagious effect was most likely between directly related family members, slightly less likely between friends, and even less likely still between acquaintances and strangers.
The researchers said: “Our results demonstrate that yawn contagion is primarily driven by the emotional closeness between individuals and not by other variables, such as gender and nationality.”
The findings have been further cemented by results from additional studies involving children with autism. Children with autism are generally less able to express empathy than other children – and were found to be less likely to pick up on the contagious effect of yawning than other children.
Experimental psychologist Dr Catriona Morrison from the University of Leeds has said that this subconscious response could shed light on the evolution of the human brain.
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