Why It's Impossible To Hum When Holding Your Nose
Go ahead, we'll wait. Grab ahold of your schnoz, your sniffer, your proboscis, and try to hum your favorite song. Or just any old song, for that matter. Maybe it's a classic childhood choice like Twinkle, Twinkle Little Star. Maybe it's something off the new Taylor Swift album. Maybe it's Ozzy Osbourne's classic opening verse line from "War Pigs" — if so, we salute you. But it doesn't matter, because no matter what you try to hum, you won't be able to do it. Hum really hard, really soft, at a high pitch, a low pitch, open-mouthed, closed-mouthed — nope, no can do.
This fun little experiment — something between a party trick and the world's most harmless dare — falls under the same "Did ya' know?" category as other bodily factoids. For instance, as Christian Science Monitor outlines, did ya' know that if you try to stand up out of a chair without bending forward, you can't? There are some variations on this, like crossing one's arms before standing, as Buzzfeed shows. It all deals with one's "center of mass," per the University of Guelph, often incorrectly called "center of gravity."
And the humming while holding your nose thing? There's a simple reason that you can't. Go ahead and try humming again, but this time don't pinch your nose closed — just place your fingers in front of your nostrils and feel the air. That's right, you're exhaling. Just like talking, singing, or even breathing, humming requires you to exhale.
The air must flow
There really isn't much more to say about not being able to hum with your nose closed, since people reading this article are presumably alive and also therefore breathing. If you've spent any time breathing, you know how the whole thing goes: breathe in, breathe out, breathe in, breathe out. Couldn't get any simpler, right? That being said, folks might have never realized that producing sound — talking, singing, humming, etc. — requires exhalation.
The London Singing Institute goes into a bit of detail about how people produce sound, which all comes from the vocal chords in the throat. Producing sound requires passing air through the vocal chords, kind of like the way wind passes through a sail. The sail flaps around a bit, and so do the vocal chords. Voila: instant vibration. When someone exhales without creating any vocalizations, the air doesn't pass through the vocal chords. All of this happens largely unconsciously, as no one sits around thinking to themselves, "I am now going to produce speech, therefore I am going to redirect the air flow coming out of my lungs through my vocal chords rather than bypass those vocal chords and push the air directly through my throat."
As The World explains, vocal chords produce sound because they reverberate in a box: one's own body. Otherwise, vocal chords would just sort of wobble around like a plucked rubber band. The box, though, needs an unclasped nasal passage for air to escape.
The nasopharyngeal connection
Speaking of rubber bands vibrating in boxes, go ahead and hum again with your mouth closed. Where is the vibration located? Folks would most likely say, "In my throat," which is correct. Now, hum again and open your mouth. It's possible to continue humming in the throat rather than push the sound forward and sing, right? But, you'll notice that the vibration travels to the back of the nose at the intersection of the throat and palate. The tone shifts a bit, too, and becomes somewhat nasal. That's because humming, as opposed to singing, always pushes air through the nose. There's no such thing as humming through your mouth — that's called singing.
All of this can sound bizarrely complex for such a simple-seeming thing, and has to do with the surprisingly intricate structure of the human pharynx. As a diagram on the National Library of Medicine shows us, the pharynx includes everything from the trachea and esophagus in the throat — used to inhale and ingest, respectively — all the way up through the big nasal cavity hanging out under the eyes. And all this humming and vibration stuff? Humming pushes air into the nasopharynx, the topmost section of the throat that connects to the nasal passage, as the Cleveland Clinic details. The passage quivers, and folks hum. And just like the pharynx itself, this goes to show that even the simplest answers about the human body go far deeper than you might realize.