Yawns may be contagious because they serve as a social cue that helps regulate the brain's oxygen and carbon dioxide levels among individuals in a group. The article mentions that when humans are tired, they stop taking deep breaths, leading to a build-up of carbon dioxide, which can signal the need to yawn. Douglas Parham states, "A yawn might be a special kind of respiration," as it allows us to quickly intake oxygen while expelling carbon dioxide. This suggests that yawning may not only be a response to individual need but may also facilitate group alertness and synchronization through shared physiological changes. This reasoning is logical because it connects the physiological function of yawning to the social behavior observed when people yawn in the presence of others.
"Why are yawns contagious? We asked a scientist"
by Teresa Carey
One theory argues that when humans are tired, we stop taking deep breaths, which causes a build-up of carbon dioxide in the body, said Douglas Parham, a speech scientist at Wichita State University. A yawn might be a special kind of respiration, Parham said. It builds up oxygen quickly, while expelling carbon dioxide, even more than a deep breath.
Excess carbon dioxide and other chemical changes, such as a drop in oxygen or increase in a compound called adenosine, could also act as “yawn gates,” said James Giordano, a neuroethicist and neuroscientist at Georgetown University. These chemicals send out a signal that triggers a yawn. By yawning, we compress the muscles of the face, driving oxygen-enriched blood to the brain, Giordano said.
Other proposals state the purpose of yawning is to cool the brain, or to stretch internal organs like tissues and lungs, helping the body to liven up.
Despite being a fundamental part of our lives, information on yawning is thin, said Thomas Scammell, a neurologist at Harvard Medical School who studies sleep. But he added that yawning is a primitive reflex among many animals that originates in the brain stem.
1 of 4
Question
Use this excerpt from the "Why are yawns contagious? We asked a scientist" article to answer the question.
Based on the information in the article, make a logical inference about why yawns are contagious. In 3–5 sentences, provide specific evidence from the text to support your inference and explain why your reasoning is logical and valid.
(4 points)
Short Answer Rubric (4 points)
Points Awarded Criteria
4
The answer is very clear.
The answer is fully supported by details.
There may be a few errors in grammar, usage, or mechanics. Errors do not interfere with meaning.
3
The answer is mostly clear.
The answer is supported by mostly relevant details.
There are a few errors in grammar, usage, or mechanics. Errors do not interfere with meaning.
2
The answer is somewhat clear.
Details are weak or not related.
There are some errors in grammar, usage, and mechanics. Errors interfere with meaning.
1
The answer is not clear.
There are few or no supporting details.
There are many errors in grammar, usage, and mechanics. Errors interfere with meaning.
0 The question is not answered.
1 answer
1 answer