Yawns and Hiccups

From Cleveland Clinic:

Throughout the ages, people have wondered and invented explanations – some reasonable and some quite far-fetched – as to why we yawn, hiccup and get goosebumps.

Centuries ago, people claimed hiccups meant a growth spurt for children, that you should cover your mouth during a yawn to prevent your soul from leaving the body, and that goosebumps make your hair grow faster.

Most people in the modern world don’t have those beliefs, yet the majority of them still don’t know why our bodies behave in these ways.

How and why goosebumps happen

Goosebumps – everybody gets them. When you’re cold, afraid, shocked, anxious or even inspired, goosebumpscan suddenly pop up all over the skin.

“Goosebumps occur when the tiny muscle located at the base of each hair follicle contracts, causing the hair to stand on end. These goosebumps, or piloerections, have no beneficial function in humans,” says Daniel Neides, MD.

For furry animals, goosebumps help create warmth against a cold environment. They also appear during a fight-or-flight situation.

“In the animal model, hair standing on end creates insulation against the cold. Additionally, when an animal finds itself in danger, the raised fur coat creates a visual of a bigger animal and may scare off predators,” Dr. Neides says.

Humans don’t have enough body hair for goosebumps to have any insulating effect. And goosebumps won’t scare off any would-be predators, either.

The real facts about hiccups

Most people have experienced the uncomfortable, sometimes quite noisy condition known as hiccups. “When the diaphragm — a muscle situated between the lungs and the stomach — becomes irritated, it begins to spasm. This spasm causes what is commonly known as hiccups,” explains Dr. Neides.

Hiccups occur because of a disturbance in the nerve pathways that lead from the brain to the diaphragm, explaining why they sometimes occur during emotional situations or temperature changes. They may begin after you swallow too much air, eat too quickly or too much, or experience excitement or anxiety.

“Hiccups are usually short lived. Persistent hiccups, lasting for several days or more, may indicate the presence of a medical issue that needs attention,” warns Dr. Neides. “Sometimes certain diseases or even a medical procedure, especially those involving anesthesia, can cause prolonged bouts of hiccups,” he adds.

You’ve probably heard about numerous remedies for curing hiccups, but none of these has any scientific basis, according to Dr. Neides. However, he says, some anecdotal evidence suggests that an increase in carbon dioxide may help. Holding your breath or breathing into a paper bag increases carbon dioxide levels in the lungs and may relax the diaphragm, stopping the spasms and, thus, the hiccups.

Learn the truth of why you yawn

You may yawn when you feel sleepy, bored or when someone around you yawns. Sometimes a yawn comes on for no apparent reason at all. Many people have heard the theory that people yawn because the brain needs more oxygen. This simply isn’t true.

“A new study reports that yawning is a mechanism involved in thermoregulation of the brain,” Dr. Neides says. The researchers found yawns are preceded by increases in brain temperature.

“Just like your computer has its own cooling mechanism to keep it from overheating, your body’s computer, the brain, uses yawning to regulate its temperature,” he says.

The study added to other research findings that both spontaneous and contagious yawns arise out of an underlying mechanism involved in brain temperature regulation. So if you yawn after seeing someone else yawn, it’s likely because you’re both in the same area and, thus, exposed to the same temperature environment.

The same goes for when you feel sleepy or bored. Sleep cycles, boredom and stress are associated with temperature fluctuations in the brain.

Now you know the truth about why you experience goosebumps, hiccups and yawns. The next time you see someone with the hiccups, or one of these other involuntary bodily responses, you can let them in on the facts.