WASHINGTON -- Although there are long-standing myths and mysteries surrounding yawning, researchers are starting to better understand it.
According to The Wall Street Journal, the reason behind yawning might lie deep within the brain.
Reaction times and memory are negatively impacted when the brain heats up beyond the ideal 98.6 degrees Fahrenheit, and taking a deep breath of air cools the blood that flows to the brain.
"A single yawn improves cognitive functioning by bringing brain temperatures to optimal levels," Andrew Gallup, an evolutionary psychologist, tells the Wall Street Journal during a Skype interview.
That may explain why people yawn more during the summer, and why many yawn when they are experiencing a lot of stress or anxiety.
According to Gallup, there are still many unanswered questions.
"No one really quite knows why yawning is contagious," Gallup said.
Though, according to recent research, if yawning indeed keeps the brain functioning at optimal levels, contagious yawning may have evolved in animals as a way to keep an entire group alert.
"The spreading of that behavior across the group could enhance overall group vigilance," Gallup said.
One thing is for certain -- yawning is a complex response, and it does not happen simply because we are tired, bored or in need of oxygen.
"Research has found no link between different levels of oxygen or carbon dioxide in the air and any influence on yawning frequency," Gallup said.
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