Autism and schizophrenia sufferers are reportedly less able to catch yawns
, researchers said, so understanding the genes that might code for contagious yawning could illuminate new pathways for treatment.
Individuals with autism or schizophrenia - which involve social skills that are impaired - exhibit less contagious yawning even though they still yawn
spontaneously, explain the investigators.
When verified across multiple testing sessions, the number of yawns
was consistent, demonstrating that contagious yawning is a very stable trait.
The contagiousness of yawns
suggests there may be a deeper social context for pandiculation as well.
So, if we didn't yawn
, according to this theory, taking a deep breath would become harder and harder.
In total, 56 yawns
and 27 non-yawn
mouth openings were observed from 58 scans.
Everyone knows when one person yawns
it can set others off - but why the phenomenon occurs is little understood.
The first I should like to mention is a paper called Dogs Catch Human Yawns
(by R M Joly-Mascheroni et al in Biology Letters, 2008) which reported an experiment in which 29 dogs watched a human yawning at them and the experiments counted how many of them yawned
Senju thinks it is likely that dogs' yawns
induce yawning in humans.
Monika Smith (trans) The Big Yawn
Gecko Press, 2009 32pp NZ$18.
The man yawns
widely, then seconds later the dog yawns
When some one yawns
, his or her alertness is heightened, as the sudden intake of oxygen increases the heart rate, rids the lungs and the bloodstream of the carbon dioxide build-up, and forces oxygen through blood vessels in the brain, while restoring normal breathing and ventilating the lungs.