The Wonderful Reason Babies Hiccup So Much

[♪ INTRO] *hic* Ah, hiccups. We’ve all been there. Usually, they’re no big deal – unless
you’re one of the 4,000 Americans admitted to the hospital every year for hiccups, or you’re that Iowa
farmer who hiccuped for 68 years straight. Still, even the occasional bout of hiccups
can be annoying. And as you hold your breath or gulp down water to try to make them stop, you may wonder: Why is this happening to me? Well… scientists don’t really know. But teeny little baby hiccups might provide
a clue. Hiccups mainly involve the diaphragm (that dome-shaped muscle below your lungs that drives your breathing) and the glottis (the opening between your vocal cords). Basically, they occur when your diaphragm
spasms, causing you to rapidly inhale. That forces your glottis to audibly slam shut. And everyone experiences them at some point
— they’re one of the first things we do in
the womb. Fetuses begin hiccuping at just nine weeks
old. And they continue to hiccup a ton (between 8 and 14 times per hour!) until they’re about 24 weeks old. Then, things settle down somewhat. Though, young babies still hiccup a bunch, especially if they were delivered early. For example, preterm newborns (those born
before 37 weeks) spend an average of 15 minutes a day hiccuping! Which got scientists at University College
London thinking that there might be a developmental
purpose behind all this convulsing. So for a study published in December 2019, they outfitted 13 newborns with a cute cap
of electrodes and monitored their hiccups. They found that every time a baby’s diaphragm
contracted, it triggered two large brainwaves, then a
third brainwave. The third wave is the most interesting, because it looks similar to the brainwave
created when we hear a noise. So, the researchers think the babies may be
hearing the “hic” and connecting it in their brains with the sensation of their diaphragm contracting. This may allow their brains to form neural
circuits which help them sense what’s happening with
their internal organs. The fancy scientific term for this ability
is interoception, and it’s how you know you’re having trouble
breathing, or your stomach feels full, or your heart
is beating fast. Creating these nerve connections between the brain and the diaphragm could also help
them learn to control their breathing. The same scientists think something similar happens when fetuses kick in the womb. Basically, those kicks may help them create
mental maps of their bodies so they can sense where their
legs are, and, eventually, learn to make voluntary movements. So why do adults hiccup if our brains don’t need to learn how to breathe anymore? That’s a good question. It could simply be that we can’t get rid of this reflex after it’s served its purpose. But who knows? There aren’t a whole lot of studies of run-of-the
mill occasional hiccuping in adults since, well, it’s not really something doctors are concerned
about. So maybe if scientists investigated hiccups
more, they’d find these spasms have a weirdly amazing purpose in adults, too. Thanks for asking about hiccups, Michelle
and Anne! And thanks in general to all of our patrons
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one. So your question could be next! [♪ OUTRO]