Asked by: Luke Ward, London
Yawning is contagious for both children and adults. Even certain animals, such as dogs, can catch a yawn! One study of adults showed that yawning becomes less contagious with age. Furthermore, children under the age of four and children with autism spectrum disorders may be less likely to yawn when they see others doing so. There are many theories as to why yawning is contagious. One possibility is that it helps synchronise people within a group, by signifying that it is bedtime, for example. Another suggests that it helps regulate our brain temperature. It may also be a sign of empathy – although not all studies support this idea.
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