Psychologist Publishes Research on Yawning
Why do we yawn? An evolutionary psychologist at SUNY Oneonta may have the answer.
Previously, scientists thought that yawning was a mechanism for increasing oxygen to the blood, but that theory was debunked in 1987. Now, a new study led by SUNY Oneonta Assistant Professor of Psychology Andrew Gallup supports the theory that yawning is a brain cooling mechanism.
Gallup worked with a team of researchers from the University of Vienna, Austria, and Nova Southeastern University to show that yawning is part of a suite of thermoregulatory mechanisms, much like sweating, that keep the brain functioning optimally. The results of the study are published this month in the scientific journal Physiology & Behavior.
A number of factors, including sleep cycles and stress, are associated with changes in brain temperature, and these fluctuations can hamper mental efficiency and alertness. That’s where yawning comes in. Gallup’s thermoregulatory theory suggests that yawning functions to cool the brain, in part, due to the heat exchange that happens as we stretch the jaw and take a deep inhalation of air.
It’s widely accepted that yawning is contagious. Even animals—including domesticated dogs, chimpanzees and parakeets — have been documented to show contagious yawning. Gallup’s research goes a step further, suggesting that both spontaneous and contagious yawning occur within a narrow “thermal window.” At temperature extremes, people yawn less frequently —even when they see others yawn.
To test this theory, Gallup’s team measured contagious yawning frequencies of pedestrians outdoors in Vienna, Austria, during both the winter and summer months, and then compared these results to an identical study conducted in Tucson, Arizona. Results showed that contagious yawning was constrained to a range of temperatures around 68 degrees Fahrenheit. In Vienna, people yawned more in summer than in winter, whereas in Arizona, people yawned more in winter than in summer.
The latest study is an incremental piece in a body of work Gallup has done on the topic. For example, previous studies by Gallup have shown that brain and skull temperatures rapidly decrease following yawns. He first became interested in yawning as an undergraduate student at the University at Albany. “I was really shocked to find out that no one had a clear understanding of why we yawn,” he recalls. “It’s something that we do every day, multiple times, and something that all vertebrates do … but why do we do it?”
Gallup wrote his honors thesis on the thermoregulatory theory in 2007, and has since done extensive research on contagious and spontaneous yawning in both animals and humans.
There are several implications of Gallup’s work. “First and foremost, it improves our basic understanding of this behavior that is ubiquitous,” he says. “A better understanding of why we yawn could also open people’s minds. This is a behavior that is completely spontaneous and involuntary. The fact that it could be interpreted as disrespectful is outrageous.”
In addition, if yawning is accepted as a thermoregulatory mechanism, doctors could use excessive yawning as a diagnostic indicator for certain medical conditions, such as multiple sclerosis, where excessive yawning is often a symptom.
Gallup came to SUNY Oneonta in fall 2013. He earned a B.A. with honors in Psychology and a minor in Anthropology from the University at Albany and a Ph.D. in Biological Sciences with a graduate certificate in Evolutionary Studies from Binghamton University. Following this, he performed postdoctoral research in the Department of Ecology and Evolutionary Biology at Princeton University, worked as a Visiting Researcher in the Center for Insect Science at the University of Arizona and was a Visiting Assistant Professor of Psychology at Bard College.
As an evolutionary psychologist, Gallup applies the principles of evolutionary theory to understand and predict various aspects of behavior. In addition to the yawning studies, recent research projects include naturalistic observations of gaze-following and information transfer in crowds; experiments identifying the correlates of stone throwing accuracy; and surveys exploring geographic variation in preferences for wood smoke.
At SUNY Oneonta, he teaches a variety of psychology courses and works on research projects with small groups of students. He will continue his yawning research this summer, with a parakeet study.