An Immaterial Pathogen: Contagious Yawning and its Broader Implication
One bright sunny day, a teenage girl Ella sat near the windowsill patting the fluffy head of her beloved cat Jimmy. Staring at Jimmy’s indigo eyes with a sense of comfort, Ella started to yawn like singing a mysterious melody. Jimmy opened her mouth wide and yawned quietly seconds after. Ella’s younger sister observing in the doorway almost dropped her jawbone after the biggest yawn she’d ever experienced in her life. What’s going on here? Ella, her sister, and Jimmy just shared the experience of an immaterial contagion.
Everybody yawns, so do animals such as dogs, cats, chimpanzees, or even sharks. Multiple factors that trigger a yawn involve fatigue, stress, boredom, and seeing someone beside you yawn. Even if you, without fatigue, simply hear the voice of someone else yawning, there is a great chance you will yawn uncontrollably or even more intensely if you urge yourself to stop.
However, both psychological and physiological reasons for contagious yawning remain a mystery. According to psychologist Gordon Gallup, contagious yawning may help group members become alert and defend against attackers. It might also reinforce social bonds as an imitative herd behavior among humans or cross-species, similar to if you smile back at someone when they smile at you, a possible way to communicate emotions and feelings.
Neurologists define contagious yawning as a common form of echophenomena, an automatic imitation of others’ words or actions. It is triggered by primitive reflexes in our brain’s primary motor cortex, an area responsible for movements involving motor neurons. Researchers from the University of Nottingham demonstrated significant progress in explaining and understanding the neural basis of contagious yawning based on the mirror neurons system in humans. The experts incorporated transcranial magnetic stimulation, a noninvasive brain activator to 36 adults while playing them videos of people yawning.
Researchers found the variability and propensity to yawn is individualized and determined by cortical excitability, the strength of the response of cortical neurons under given stimuli, and psychological inhibition in the primary motor cortex. In other words, the propensity to be affected by contagious yawning is like a hardwire in an individual’s brain.
The more you resist yawning after you see or hear somebody yawning beside you results in more frequent yawning or yawning in stifled expression.
According to Georgina Jackson, a professor of cognitive neuropsychology at the Institute of Mental Health, “Using electrical stimulation we were able to increase excitability and in doing so increase the propensity for contagious yawning.” This unexpected realization could have an impact on the quality of life for many people. Studies on contagious yawning are very important in understanding and treating clinical cases associated with motor excitability and echophenomena such as epilepsy, autism, and Tourette Syndrome, which are connected to increase in cortical excitability and/or decrease in physiological inhibition. Above all, research in contagious yawning helps us understand human psychological behavior and discover the evolutionary myths of our own species in the near future.
Works Cited
A Neural Basis for Contagious Yawning
Why Do We Yawn? Physical and Psychological Reasons.
A Calm Look at the Most Hyped Concept in Neuroscience - Mirror Neurons