Fetuses yawn repeatedly in the womb, a new study finds. The reasons are as yet unknown. Are they losing sleep? Are they stressed or overworked? Do they find their limited entertainment options insufficiently stimulating? The researchers suggest that the yawning is linked to brain development, but also admit it’s still a mystery why anyone yawns, before or after birth. It’s safe to say, however, that contagious yawning — something humans share with dogs and chimpanzees — is not a factor in the womb.
Almost all vertebrates yawn, including fish. If the James–Lange theory of emotion is to be credited, yawning reinforces bodily consciousness. Or so suggests the author of a 2006 article in the journal Medical Hypotheses.
Yawning can be seen as a proprioceptive performance awareness which inwardly provides a pre-reflective sense of one’s body and a reappraisal of the body schema. The behavioral consequences of adopting specific regulatory strategies and the neural systems involved act upon attention and cognitive changes. Thus, it is proposed that yawning is a part of interoceptiveness by its capacity to increase arousal and self-awareness.
I like the idea that nascent self-awareness finds expression in yawning. “I yawn, therefore I am”?