I used to have a model of breathing that went something like this: when breathing in, the lungs somehow get bigger, creating lower air pressure inside the lungs causing air to flow in. Then when breathing out the lungs get smaller, creating higher air pressure inside the lungs and causing air to flow out. How do the lungs get bigger and smaller? Eventually I learned that there’s a muscle called the diaphragm that is attached to the bottom of the lungs (??) that pulls or pushes the lungs. If I keep my nose plugged but my mouth open, the air will travel through my mouth. If I keep my mouth closed but my nose open, the air will travel through my nostrils. So far, so good.
Then a few days ago, I noticed that if I keep both my nose and mouth open, I could choose to breathe in solely through one or the other. This… doesn’t make sense, according to the model. The model would predict that the air just flows through both pathways, maybe preferentially going through the mouth since that seems like the larger pathway.
So something is clearly wrong with how I think about breathing. Is there some sort of further switch inside that blocks one of the pathways? Does the nose or the mouth contain variable-size cavities that can control air pressure to direct the flow? I still have no idea. I’m eventually going to look it up, but I might think about this for a little bit longer (or maybe someone here will tell me).
I thought this was a pretty interesting example of how the explanations you hear about seemingly-basic things are easy to accept but don’t make sense on further reflection. But it’s hard to notice the flaw too. In my case, after a recent ENT visit where I was told my nasal passages are inflamed, I’ve been putting more effort into consciously breathing through my nose. Then one day I woke up and as soon as I woke up I did something like consciously breathe through my nose with mouth closed, and then somehow I opened my mouth but then still tried to breathe through my nose (or maybe it was that I noticed I was breathing through my mouth, and since I was still waking up I didn’t bother to close my mouth and just tried to breathe through my nose with my mouth open), and was surprised this was even possible.
I did some quick experimentation. I found that if my tongue doesn’t block my mouth I can only breathe through my mouth and if it does I can only breathe through my nose.
I then didn’t block my mouth airway with my tongue and blocked my mouth with my hand. It seems air doesn’t go through my nose in that case unless I breathe in really hard, in which case I hear and feel something opening in the back of my nose. I’m guessing there is another valve in the nose.
If you had allergies growing up you’d already know all of this..
I found that if my tongue doesn’t block my mouth I can only breathe through my mouth and if it does I can only breathe through my nose.
Huh, this isn’t what happens when I try it. If I keep my tongue out or at the base of my mouth, I can still definitely choose whether to make the air go through my nose or mouth. If I try to block my mouth with my tongue, that does obstruct the airflow through my mouth but I can still breathe mostly okay (even if I plug my nose).
I used to have a model of breathing that went something like this: when breathing in, the lungs somehow get bigger, creating lower air pressure inside the lungs causing air to flow in. Then when breathing out the lungs get smaller, creating higher air pressure inside the lungs and causing air to flow out. How do the lungs get bigger and smaller? Eventually I learned that there’s a muscle called the diaphragm that is attached to the bottom of the lungs (??) that pulls or pushes the lungs. If I keep my nose plugged but my mouth open, the air will travel through my mouth. If I keep my mouth closed but my nose open, the air will travel through my nostrils. So far, so good.
Then a few days ago, I noticed that if I keep both my nose and mouth open, I could choose to breathe in solely through one or the other. This… doesn’t make sense, according to the model. The model would predict that the air just flows through both pathways, maybe preferentially going through the mouth since that seems like the larger pathway.
So something is clearly wrong with how I think about breathing. Is there some sort of further switch inside that blocks one of the pathways? Does the nose or the mouth contain variable-size cavities that can control air pressure to direct the flow? I still have no idea. I’m eventually going to look it up, but I might think about this for a little bit longer (or maybe someone here will tell me).
I thought this was a pretty interesting example of how the explanations you hear about seemingly-basic things are easy to accept but don’t make sense on further reflection. But it’s hard to notice the flaw too. In my case, after a recent ENT visit where I was told my nasal passages are inflamed, I’ve been putting more effort into consciously breathing through my nose. Then one day I woke up and as soon as I woke up I did something like consciously breathe through my nose with mouth closed, and then somehow I opened my mouth but then still tried to breathe through my nose (or maybe it was that I noticed I was breathing through my mouth, and since I was still waking up I didn’t bother to close my mouth and just tried to breathe through my nose with my mouth open), and was surprised this was even possible.
This is the kind of question that ChatGPT can answer really well.
I did some quick experimentation. I found that if my tongue doesn’t block my mouth I can only breathe through my mouth and if it does I can only breathe through my nose.
I then didn’t block my mouth airway with my tongue and blocked my mouth with my hand. It seems air doesn’t go through my nose in that case unless I breathe in really hard, in which case I hear and feel something opening in the back of my nose. I’m guessing there is another valve in the nose.
If you had allergies growing up you’d already know all of this..
Huh, this isn’t what happens when I try it. If I keep my tongue out or at the base of my mouth, I can still definitely choose whether to make the air go through my nose or mouth. If I try to block my mouth with my tongue, that does obstruct the airflow through my mouth but I can still breathe mostly okay (even if I plug my nose).