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  • Charles Osborne began to hiccup in 1922 after a hog fell on top of him.

  • He wasn't cured until 68 years later

  • and is now listed by Guinness as the world record holder

  • for hiccup longevity.

  • Meanwhile, Florida teen Jennifer Mee

  • may hold the record for the most frequent hiccups,

  • 50 times per minute for more than four weeks in 2007.

  • So what causes hiccups?

  • Doctors point out that a round of hiccups often follows from stimuli

  • that stretch the stomach,

  • like swallowing air

  • or too rapid eating or drinking.

  • Others associate hiccups with intense emotions

  • or a response to them:

  • laughing,

  • sobbing,

  • anxiety,

  • and excitement.

  • Let's look at what happens when we hiccup.

  • It begins with an involuntary spasm or sudden contraction of the diaphragm,

  • the large dome-shaped muscle below our lungs

  • that we use to inhale air.

  • This is followed almost immediately by the sudden closure of the vocal chords

  • and the opening between them,

  • which is called the glottis.

  • The movement of the diaphragm initiates a sudden intake of air,

  • but the closure of the vocal chords stops it from entering the wind pipe

  • and reaching the lungs.

  • It also creates the characteristic sound: "hic."

  • To date, there is no known function for hiccups.

  • They don't seem to provide any medical or physiological advantage.

  • Why begin to inhale air only to suddenly stop it from actually entering the lungs?

  • Anatomical structures,

  • or physiological mechanisms, with no apparent purpose

  • present challenges to evolutionary biologists.

  • Do such structures serve some hidden function that hasn't yet been discovered?

  • Or are they relics of our evolutionary past,

  • having once served some important purpose

  • only to persist into the present as vestigial remnants??

  • One idea is that hiccups began

  • many millions of years before the appearance of humans.

  • The lung is thought to have evolved as a structure to allow early fish,

  • many of which lived in warm, stagnant water with little oxygen,

  • to take advantage of the abundant oxygen in the air overhead.

  • When descendants of these animals later moved onto land,

  • they moved from gill-based ventilation to air-breathing with lungs.

  • That's similar to the much more rapid changes faced by frogs today

  • as they transition from tadpoles with gills

  • to adults with lungs.

  • This hypothesis suggests that the hiccup is a relic of the ancient transition

  • from water to land.

  • An inhalation that could move water over gills

  • followed by a rapid closure of the glottis preventing water from entering the lungs.

  • That's supported by evidence

  • which suggests that the neural patterning involved in generating a hiccup

  • is almost identical to that responsible for respiration in amphibians.

  • Another group of scientists believe that the reflex is retained in us today

  • because it actually provides an important advantage.

  • They point out that true hiccups are found only in mammals

  • and that they're not retained in birds, lizards, turtles,

  • or any other exclusively air-breathing animals.

  • Further, hiccups appear in human babies long before birth

  • and are far more common in infants than adults.

  • Their explanation for this

  • involves the uniquely mammalian activity of nursing.

  • The ancient hiccup reflex may have been adapted by mammals

  • to help remove air from the stomach as a sort of glorified burp.

  • The sudden expansion of the diaphragm would raise air from the stomach,

  • while a closure of the glottis would prevent milk from entering the lungs.

  • Sometimes, a bout of hiccups will go on and on,

  • and we try home remedies:

  • sipping continuously from a glass of cold water,

  • holding one's breath,

  • a mouthful of honey or peanut butter,

  • breathing into a paper bag,

  • or being suddenly frightened.

  • Unfortunately, scientists have yet to verify that any one cure

  • works better or more consistently than others.

  • However, we do know one thing that definitely doesn't work.

Charles Osborne began to hiccup in 1922 after a hog fell on top of him.

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B2 US TED-Ed hiccup air closure diaphragm entering

【TED-Ed】Why do we hiccup? - John Cameron

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    Sh, Gang (Aaron) posted on 2016/07/31
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