[HN Gopher] Ear muscle we thought humans didn't use activates wh...
       ___________________________________________________________________
        
       Ear muscle we thought humans didn't use activates when people
       listen hard
        
       Author : geox
       Score  : 226 points
       Date   : 2025-01-31 12:11 UTC (19 hours ago)
        
 (HTM) web link (www.frontiersin.org)
 (TXT) w3m dump (www.frontiersin.org)
        
       | feverzsj wrote:
       | So, movies are actually right.
        
       | mathieuh wrote:
       | Whenever I hear a noise behind me this muscle reflexively flexes
       | quite hard, especially if it's a sudden noise that makes me jump.
        
         | lttlrck wrote:
         | Yes. It's quite a distinct part of my being startled by an
         | unexpected sound, similar to hairs raising on the back on my
         | neck.
        
         | kennyadam wrote:
         | Same. Is this something not everyone experiences or just never
         | really comes up in conversation much I wonder?
        
           | dillz wrote:
           | Had to scroll surprisingly far to find this comment thread.
           | My ears sometimes react the same way on unexpected noises in
           | a silent environment. However, I can not move my ears
           | voluntarily, none at all.
        
       | datavirtue wrote:
       | All I can picture right now is a Ferengi.
        
       | mmastrac wrote:
       | I trained myself to wiggle one ear as a kid and it's exactly like
       | this. The muscle is much stronger in that ear and there's a weird
       | reflex that when something startles me from behind, the same
       | muscle that makes the ear wiggle triggers. It happens in the
       | untrained ear as well.
       | 
       | Weird phenomenon.
        
         | Gys wrote:
         | You trained it? I can wiggle each ear very visibly (and both).
         | I hardly ever do but as I remember most people can't. So i
         | always assumed it was a DNA thing.
        
           | noelwelsh wrote:
           | Not the person you're replying to, but is also trained myself
           | to do it. I basically touched the area where the muscle is,
           | tried to activate it ... time passes ... and some unconscious
           | process figured it out. Now, as a responsible parent, I use
           | my super power to troll my kids.
        
           | justanotherjoe wrote:
           | It could be both
        
           | ABS wrote:
           | I too trained it when I was in primary school after seeing a
           | class mate do it.
           | 
           | And like OP I eventually managed to control one ear (right)
           | but not the other, even to this day 40 years later
        
             | unsupp0rted wrote:
             | Same here, same ear
        
             | RajT88 wrote:
             | I can twitch my left ear independently from my right. But
             | not the right one independently. I'm sure it means
             | something. Both at the same time is easy.
        
           | phkahler wrote:
           | >> I can wiggle each ear very visibly (and both). I hardly
           | ever do but as I remember most people can't. So i always
           | assumed it was a DNA thing.
           | 
           | After reading the article I think its a "use it or lose it"
           | thing where the muscles and ability to control them atrophy
           | in our modern environment. We have more competing sounds and
           | external means to "turn up the volume" so we can hear a
           | particular thing.
        
         | gpderetta wrote:
         | I can wiggle either ear independently. It greatly annoys my
         | wife and my kids :D
        
           | iszomer wrote:
           | Me too but it annoys no one I know. Best use case is when I
           | need more bass in my IEM's.
        
           | doubled112 wrote:
           | I've always been able to wiggle my ears, but just today I
           | learned if I focus I can do one at a time. I'm 33. Thanks for
           | the useless new skill!
        
         | techjamie wrote:
         | I can also wiggle both ears and tend to do the same thing.
         | Always just thought I was weird.
        
         | awinter-py wrote:
         | useful for listening to someone through earbuds as well --
         | moving back the ear creates an air gap
        
         | RajT88 wrote:
         | I wouldn't say I trained it, but I learned to control it.
         | 
         | I do find myself pricking up my ears to hear better, not always
         | consciously.
         | 
         | FWIW, I can raise my eyebrows individually, flare my nostrils,
         | twitch my nose, and also flex some muscle which pops my ears.
         | Useless human tricks. Except popping my ears; super useful on
         | airplanes.
        
           | kstrauser wrote:
           | If you can't will your ears to pop, here's the manual way:
           | https://en.wikipedia.org/wiki/Valsalva_maneuver
        
             | abdullahkhalids wrote:
             | The method involves closing the mouth and pinching the nose
             | shut and trying to "exhale". As the wiki notes further
             | down, this can cause damage to your hearing if you do it
             | too forcefully, so use other methods first.
        
               | kstrauser wrote:
               | True, but it's really, really easy to not do it so hard
               | that you blow your eardrums out. Scuba divers do this all
               | the time.
        
               | abdullahkhalids wrote:
               | It doesn't work for me, and there is a definitely a voice
               | in my head saying blow harder.
        
             | shkkmo wrote:
             | That's a way, and perhaps the most common, but far from the
             | best. In particular, it has to be used preemptively before
             | pressure builds up.
             | 
             | https://en.wikipedia.org/wiki/Ear_clearing
        
           | Alex-Programs wrote:
           | I have a lot of trouble on airplanes. How did you learn to do
           | that?
        
             | RajT88 wrote:
             | I don't know? I was really young, and as far as I can
             | recall I just did it one day.
             | 
             | I always thought it was a muscle in my ears, but I remember
             | looking it up, and it's actually farther back like behind
             | your throat or something. I can't do just one ear at a
             | time, it's all or nothing.
        
               | abdullahkhalids wrote:
               | Someone linked this wiki page [1] in the thread. This
               | might be it.
               | 
               | > The effectiveness of the "yawning" method can be
               | improved with practice; some people can achieve release
               | or opening by moving their jaw forward or forward and
               | down, rather than straight down as in a classical
               | yawn,[6] and some can do so without moving their jaw at
               | all by activating the tensor tympani muscle, which is
               | heard by the individual as a deep, rumbling sound.
               | 
               | > During swallowing or yawning, several muscles in the
               | pharynx (throat) elevate the soft palate and open the
               | throat. One of these muscles, the tensor veli palatini,
               | also acts to open the Eustachian tube. This is why
               | swallowing or yawning is successful in equalizing middle
               | ear pressure.
               | 
               | [1] https://en.wikipedia.org/wiki/Valsalva_maneuver
        
           | NitpickLawyer wrote:
           | > and also flex some muscle which pops my ears. Useless human
           | tricks.
           | 
           | Also useful when you're diving. I can equalise without
           | holding my nose for the first 10-15m, just by doing the thing
           | with the ears. Doesn't work all the way down tho...
        
           | saltcured wrote:
           | On the other end, I have the ability to voluntarily move my
           | big toe away from the other toes in the horizontal plane of
           | the foot. Like splaying toes, but just swinging the big toe
           | sideways while the others are at rest.
           | 
           | But, I can only do this on my right foot. It's like I have
           | awareness of a muscle and tendon there that is just absent on
           | the other foot. It was weird to realize this asymmetry at
           | first when I was young.
        
         | jannyfer wrote:
         | I can't control wiggling my ears, but I also have felt my ears
         | perk up when listening to strange sounds. Sometimes accompanied
         | by goosebumps and ASMR.
        
         | tim333 wrote:
         | >weird reflex that when something startles me from behind
         | 
         | If you have cats and make a noise behind the ears automatically
         | swivel back. I guess we must have something live that in our
         | evolutionary past.
        
         | DamnInteresting wrote:
         | When I was a lad, I spent some time in front of a mirror trying
         | to teach myself to move my eyebrows independently, like Spock.
         | I eventually succeeded, but in the process I also learned how
         | to move my ears. One downside is that these ear muscles began
         | to involuntarily try to help. For instance, if I am looking
         | down while wearing glasses, my ears contract to grip the
         | glasses so they don't fall off, and after a while these seldom
         | used muscles ache from the effort.
        
           | euroderf wrote:
           | It was only at the age of 50-something that I found out that
           | my ability to move my eyebrows independently is not a general
           | population thing. Amaze! Also FWIW I can wiggle both my ears,
           | and independently too. Is there a way to make money from this
           | ?
        
             | Aachen wrote:
             | Huh, how is it not a general population thing? To raise an
             | eyebrow is a common expression
        
               | lemonberry wrote:
               | I think he means alternating raised eyebrow. Raising my
               | left eyebrow is easy but my right requires some
               | significant contortion of my face to achieve.
        
               | euroderf wrote:
               | A quick googling reveals: "About a third of all people
               | can raise one eyebrow: left or right. [..] But the
               | ability to raise both eyebrows separately is much rarer.
               | If you're not among them, that's because you cannot yet
               | control and move the corresponding muscles."
        
             | yapyap wrote:
             | There probably is a way to make money off this, but while
             | doing so I'm thinking you also would be selling some
             | dignity along with it.
        
               | euroderf wrote:
               | Isn't that true of more work than any of us care to admit
               | ?
        
               | bluSCALE4 wrote:
               | Now more than ever.
        
               | moi2388 wrote:
               | I generally just short my dignity.
        
           | Tool_of_Society wrote:
           | Yup I have the same issue with the aching muscles.
        
           | Galatians4_16 wrote:
           | Keep at it, those ear muscles will be benching solid steel
           | glasses in no time!
           | 
           | Remember; Pain is weakness leaving the body.
        
           | lilyball wrote:
           | I did the same thing as a teenager, I taught myself to waggle
           | each eyebrow independently, but I never learned to move my
           | ears. I didn't realize that was even a learnable skill.
        
           | m463 wrote:
           | There was a movie where Jack Black does the wave with his
           | eyebrows.
           | 
           | seek the wave, grasshopper.
        
         | kstrauser wrote:
         | My ears won't move but I can flip my tongue over. I assumed
         | everyone could, but nope. Bodies are so wonderfully weird and
         | adhoc.
        
         | smusamashah wrote:
         | Someone recently told me that its genetic. Not everyone can
         | control that muscle. I can, I learned it after seeing someone
         | do it by lifting eye brows. I can control it without moving
         | eyebrows now.
        
         | hinkley wrote:
         | There's a couple actors that do this. Their character gets
         | surprise or concerning news and their ears (and sometimes also
         | their scalp) moves.
         | 
         | I find it very distracting personally.
        
         | m463 wrote:
         | funny, I do that with my nose when I want to smell something.
         | So I tend to flare my nostrils when I'm smelling for something.
        
       | helge9210 wrote:
       | Science around human body movements is in its infancy. Motion
       | capture can't differentiable various muscle group activations,
       | resulting in the same motion pattern. Electric activity sensors
       | are not sensitive enough to capture individual muscle movements.
       | And there are not enough interesting subjects (top athletes,
       | performers etc) available to scientists to improve models and
       | methods.
        
         | djtango wrote:
         | It's funny because these developments come at a time where a
         | large proportion of the world no longer really uses their body
         | for their living.
         | 
         | I wonder how different our ancestors perceived the world when
         | their survival depended on their athleticism and keen senses.
         | What knowledge and skills were common that have been lost to us
         | now? There have been articles on HN about scientists
         | "discovering" humans can exert control over their pupils and
         | more and more scientists are "accepting" that echolocation in
         | humans is real and learnable.
        
           | xg15 wrote:
           | There are some fascinating stories about kids abducted and
           | raised by wolves - who, when they were eventually found and
           | brought back into human society, showed seemingly
           | "superhuman" senses of hearing and smell. The senses became
           | more normal the longer they spent time in human society
           | however.
           | 
           | Not sure how credible those stories are, but if they are,
           | this would indicate that human senses are a lot more flexible
           | than we believe they are.
        
           | sriacha wrote:
           | One of my favorite examples is the possibility of humans to
           | have magnetoreception.
        
       | roenxi wrote:
       | I'm finding the headline is remarkably annoying.
       | 
       | Evolutionary pressure is pretty brutal to things that actually
       | aren't used - building a muscle takes energy and is one more
       | thing for the body to maintain. I don't see how it is fair to say
       | "thought humans didn't use". It is always "if it has a use, we
       | aren't sure what it is yet". Nature isn't a perfect architect but
       | the odds are just much better that the use is still to be
       | discovered than that truly useless bits of the body exist.
        
         | lgeorget wrote:
         | When I read "humans didn't use", I understand that other
         | animals with which we share close common ancestors still use
         | it. Evolutionary pressure can make organs go into disuse so it
         | makes sense that we end up with unused organs.
        
           | parineum wrote:
           | Evolutionary pressure also would select for not wasting
           | energy on a useless organ.
        
             | _Algernon_ wrote:
             | The selective pressure of small unused organs may be very
             | low and virtually disappear in the stochasticity of natural
             | selection. It may take a long time for such elements to
             | disappear completely
        
           | roenxi wrote:
           | A 1% reduction in body mass is a huge advantage evolutionary,
           | especially since rather than being cut completely that mass
           | could be repurposed as more muscle for competing or more fat
           | for lean times. For something in very recent evolutionary
           | history (talking the last few thousand years), yeah sure the
           | pressure might not have optimised a wasted organ out. But for
           | any random organ? Nah, they probably have a purpose and we
           | don't know what it is yet. Otherwise there is a big advantage
           | to removing 'useless' bits. Evolutionary processes do however
           | love little random tweaks and whatnot because they serve a
           | useful purpose in weird edge cases and it is much more likely
           | we're looking at one of them in any particular case.
        
             | jjk166 wrote:
             | And the ability to breath fire would also be a huge
             | advantage, but evolution does not seek advantages, it
             | merely keeps mutations that happen to be beneficial. No one
             | has been born with a mutation that has allowed them to
             | breath fire (or if they were they obviously didn't have
             | much reproductive success) and thus we are still unable to
             | breath fire. No one who has been born with a mutation that
             | prevents the development of ear muscles has had especially
             | great reproductive success either.
        
               | roenxi wrote:
               | Well no, being able to breath fire is probably
               | evolutionarily stupid. There is no reason to think it
               | would be helpful, it'd presumably involve animals
               | building up a highly flammable concoction inside their
               | bodies and occasionally exploding. For no gain, since
               | they could do what everyone else does and gather
               | combustible material and set it alight. And flamethrowers
               | just aren't very effective weapons on average since
               | they'd tend to burn an animal's home down or be very
               | energetically demanding for no upside vs something like a
               | good pair of jaws or claws.
               | 
               | If evolution can figure out photosynthesis it can figure
               | out flammability. Flammability is actually pretty easy.
               | Even monkeys can manage it. There probably have been
               | animals that breath fire and it just didn't catch on
               | because it is wholly impractical.
        
             | dahart wrote:
             | > A 1% reduction in body mass is a huge advantage
             | evolutionary
             | 
             | That thought fails to explain the wide natural variation in
             | body mass of humans, and within each species on this
             | planet.
             | 
             | Edit: for most species being smaller is a disadvantage.
             | Mates statistically select for larger stronger individuals,
             | and larger stronger individuals are statistically better at
             | killing and defending.
        
               | JoeAltmaier wrote:
               | A little study of biology will clear that up. Species
               | inhabit different niches. They have different survival
               | strategies. Each case requires a different optimal point.
        
               | dahart wrote:
               | Please elaborate, I think you misunderstood me. Are you
               | defending the claim that 1% human body mass reduction is
               | an evolutionary advantage? Your quip about biology should
               | _maybe_ be directed at @roenxi?
               | 
               | I was talking about variation within each species, not
               | across different species. (Edited to clarify) I was
               | talking, in context as a reply to the claim that losing a
               | given vestigial organ would improve (lessen) mortality.
               | Humans, for example, have wide natural variation in body
               | mass, therefore the evidence contradicts the claim that
               | "1% reduction in body mass is a huge advantage
               | evolutionary".
               | 
               | If a reduction in body mass was an evolutionary
               | advantage, we'd be evolving to be smaller over time.
               | That's not happening. Why?
               | 
               | In fact, there is an evolutionary advantage in humans to
               | being taller and having more muscle, since these traits
               | are selected for by mates, and are beneficial for
               | hunting.
        
         | tbrownaw wrote:
         | > _I don 't see how it is fair to say "thought humans didn't
         | use"._
         | 
         | Did you not learn about "vestigal organs" in grade school?
         | 
         | Maybe consensus has changed lately, but that at least used to
         | be a thing.
        
           | roenxi wrote:
           | What, if you learn about something at school it is
           | automatically true? The same criticism applies there too.
           | They were calling things like the appendix vestigial when it
           | obviously isn't. People made a big deal about how it doesn't
           | do anything and then it turns out it does something. Who'd
           | have guessed. The so-called vestigial organs probably all
           | have uses. I'd have a much easier time believing most of them
           | do than none of them. Otherwise evolution would have done a
           | much better job of weeding them out.
        
             | tbrownaw wrote:
             | > _What, if you learn about something at school it is
             | automatically true?_
             | 
             | It's a decent indication that people thought it was true.
        
             | dahart wrote:
             | > The so-called vestigial organs probably all have uses.
             | 
             | You're right that some organs have been labeled vestigial
             | and turned out not to be, but there are other organs that
             | we know are vestigial because they don't occur in all
             | humans (same goes for other species). Evolution doesn't
             | weed things out without there being relatively strong
             | effects on survival, and some of these things don't affect
             | survival so they drift.
             | 
             | This also isn't binary. There are organs that are still
             | classified as vestigial, but have minor or secondary uses,
             | perhaps enough for evolution to keep them around, or again
             | perhaps because having them doesn't result in any
             | statistical mortality.
             | 
             | Speculating and/or carrying beliefs that contradict modern
             | evolutionary biologists probably isn't going to work out.
             | School might not be always right, but it is most of the
             | time, and it's right more often than no school, right?
             | https://en.wikipedia.org/wiki/Human_vestigiality
        
               | roenxi wrote:
               | > but there are other organs that we know are vestigial
               | because they don't occur in all humans
               | 
               | That argument is completely invalid because it picks up
               | the reproductive organs. At birth most humans don't have
               | ovaries and those are anything but vestigial. It'd also
               | mistake things like melanin production as vestigial
               | because some humans have black skin and others white,
               | when in reality it is a geographic adaption. Furthermore
               | the argument misses situations where something is
               | _sometimes_ an advantage but generally a cost, like
               | adaptions that are expensive to maintain but really help
               | against certain irregular events (like famines, pandemics
               | or more weird edge cases) or that are helpful in small
               | doses (like autism, a couple of autistic geniuses
               | floating around is a great outcome for everyone).
               | 
               | > This also isn't binary. There are organs that are still
               | classified as vestigial, but have minor or secondary
               | uses, perhaps enough for evolution to keep them around,
               | or again perhaps because having them doesn't result in
               | any statistical mortality.
               | 
               | Sure. But if vestigial doesn't mean useless then it isn't
               | relevant to my complaint against the headline and the
               | person bringing it up just made a rookie mistake.
        
               | dahart wrote:
               | I wasn't talking about reproductive organs...
               | _obviously_. How about reading some of the link I
               | provided?
               | 
               | > if vestigial doesn't mean useless then it isn't
               | relevant to my complaint against the headline
               | 
               | Having some minor use doesn't imply there's any
               | evolutionary pressure. The problem with your comment
               | about the headline is that your comment is incorrect;
               | evolution does not automatically remove things. I don't
               | know why you would go to battle with known science, but
               | good luck!
        
               | roenxi wrote:
               | So what are you talking about? And do you have an
               | argument or any evidence for why it might be so? You're
               | claiming there are organs that are vestigial because they
               | don't occur in all humans, but then you don't accept that
               | organs not occurring in all humans are vestigial. And
               | they are clearly important - several organs that don't
               | appear in all humans are absolutely critical. And you
               | accept that vestigial organs have minor uses, but you
               | don't seem to want to accept that "vestigial organs are
               | not useless" is probably a correct statement (which lines
               | up pretty well with the Wikipedia article, I might
               | observe).
               | 
               | Which parts of your comment are the parts that say
               | something? What are they saying? It appears to me that
               | you are saying there isn't any evolutionary pressure to
               | keep things that are minorly positive to keep from an
               | evolutionary perspective, which is surely a mis-read by
               | me so I'm not sure what you are trying to get at.
        
               | dahart wrote:
               | Did you read the section on the ear, or any of the
               | entries under musculature? Try
               | https://en.wikipedia.org/wiki/Darwin%27s_tubercle
               | 
               | > you don't accept that organs not occurring in all
               | humans are vestigial [...] several organs that don't
               | appear in all humans are absolutely critical.
               | 
               | Huh? Are you suggesting that female reproductive organs
               | should be considered vestigial because males don't have
               | them? That's not what vestigial means. The vestigial
               | organs that serve no known purpose and are missing in
               | some humans demonstrates the lack of criticality and
               | functionality, it demonstrates there's no human
               | dependency on them and that they actually don't have any
               | purpose. But not the other way around; a critical organ
               | like a reproductive organ missing in some humans does not
               | imply it's vestigial... _obviously_. Is that confusing or
               | hard to grasp?
               | 
               | It feels like you're trying to construct some sort of
               | semantic or logical trap to prove a point, but it seems
               | like you misunderstood me somewhere. Using reproductive
               | organs as your example is a pretty bad idea - in humans,
               | males aren't missing female organs, nor vice versa. We
               | start with the same organs, and they grow slightly
               | differently. They aren't missing.
               | 
               | What I'm saying, plain and simple, is that your claim
               | that "Evolutionary pressure is pretty brutal to things
               | that actually aren't used" is false. (According to
               | evolutionary biology, not according to me.) There is no
               | pressure to evolve unless things affect survival
               | (mortality or reproduction). Some organs evolved in the
               | past and we still have genes for them, but they no longer
               | serve their evolved purpose and also don't affect
               | mortality or mating in any significant way, and so there
               | is no force to get rid of them. We call those organs
               | vestigial. Some of them might be evolving away very
               | slowly, which not occurring in all humans might suggest,
               | and some might not - because whatever use they have is
               | not affecting survival rates enough to matter.
        
           | RajT88 wrote:
           | They taught us the appendix was one such organ. Now they are
           | thinking it actually has a use and is not at all vestigial.
           | 
           | https://en.wikipedia.org/wiki/Appendix_(anatomy)#Maintaining.
           | ..
        
             | Izkata wrote:
             | I remember the pineal gland in the brain as well, that was
             | part of why it got used as a source for psychic powers in
             | older fiction.
        
               | RajT88 wrote:
               | This was a memorable film which feature it:
               | https://en.wikipedia.org/wiki/From_Beyond_(film)
               | 
               | Based on Lovecraft, so it fits with "older fiction"
        
         | dahart wrote:
         | There is only evolutionary pressure on things that affect
         | mortality. Vestigial organs can and do exist because there is
         | no evolutionary pressure on them, because they don't affect
         | mortality.
        
       | nusl wrote:
       | There's a lot of stuff that does something after we thought it
       | didn't. I don't quite trust folk when they say "Oh, that's just
       | there in your body but it doesn't do anything."
       | 
       | I get that some stuff genuinely doesn't because evolution
       | deprecated it, but others we might not yet understand well enough
       | to know this for sure.
        
         | phkahler wrote:
         | >> I don't quite trust folk when they say "Oh, that's just
         | there in your body but it doesn't do anything."
         | 
         | If you expand that to "You don't need that" it covers the
         | appendix, spleen, tonsils, wisdom teeth (even incisors can be
         | removed to make room) and probably some other things. I'm in
         | favor of keeping all your parts unless absolutely necessary, as
         | all of these things seem to have at least marginal purpose.
        
           | kstrauser wrote:
           | I generally agree, but:
           | 
           | 1. They used to yank everyone's tonsils at any provocation.
           | There was a swing back to trying never to take them. I wish
           | my pediatrician would've had mine removed after my nth
           | tonsillitis so I didn't have to have them out in my 30s. That
           | was fun.
           | 
           | 2. Having had an emergency appendectomy, I'm sympathetic to
           | the notion of proactively snipping them any time you happen
           | to be in there anyway. Getting a hernia fixed? Oh hey, let's
           | grab the appy while we're at it!
        
             | simianparrot wrote:
             | Except the appendix is an important organ. It has a high
             | concentration of immune tissue and supports the immune
             | system in the gut, and it's also a "safe house" for
             | beneficial bacteria in the case of food poisoning or other
             | gut "clearing" events.
             | 
             | It absolutely should not be just nipped out proactively.
        
               | 1propionyl wrote:
               | Makes me wonder what we'd uncover with systematic
               | longitudinal studies (within the same culture, rather
               | than comparing populations with distinct cultures and
               | genetic bases) on effects of male genital mutilation.
        
               | kstrauser wrote:
               | Those are all true. However, appendicitis is still the
               | most common abdominal surgery worldwide[0] and lots of
               | people still die of it. It's easy to make the case that
               | someone already undergoing abdominal surgery where the
               | surgeon has ready access to it could have long-term lower
               | health risk by removing it.
               | 
               | If you live in a country with excellent healthcare and
               | you're never far from a hospital, the calculus is a bit
               | different. You'll probably be fine. If you regularly find
               | yourself far away from modern medical clinics, it's
               | easier to defend the idea.
               | 
               | I had appendicitis as a kid. If you've never experienced
               | it, trust me, you don't want it.
               | 
               | [0] https://pmc.ncbi.nlm.nih.gov/articles/PMC9945388/
        
               | wongarsu wrote:
               | If you practice good food safety and hygiene (and live
               | around people who do the same) then removing the appendix
               | during unrelated surgeries or even preemptively before
               | long stays at a place without emergency healthcare can be
               | beneficial.
               | 
               | It's a bit of a Chesterton's Fence situation: the
               | appendix is really useful, but for you and me the benefit
               | was much larger 300 years ago than it is today. Today the
               | benefit is small enough that you can remove it with only
               | minor considerations (like being more cautious about your
               | gut microbiome, and having a slightly worse immune
               | system)
        
         | AnthonBerg wrote:
         | My favorite - this is to some degree my interpretation though!
         | - my favorite is the _default mode network_ , a kind of
         | constellation of brain activity.
         | 
         | It's called the _default mode network_ because they found it
         | through magnetic resonance imaging or something like this, and
         | this activity pattern was the first pattern they saw!... A-ha!
         | This is the _default mode network_! The default! The default
         | mode! Yes!... the activity pattern in the brain of a human who
         | has been persuaded to go into a very tight-fitting tube and is
         | there all alone and it's not pleasant.
         | 
         | The default mode is activated during introspection and social
         | isolation and among the things it does is generate the
         | sensation of being something which is distinctly not part of
         | the rest of the world.
        
           | ulbu wrote:
           | this is so interesting.
           | 
           | it's not the first nor the last time wish that communities
           | would not refrain from changing terminology. fitness is as
           | important as accuracy and we shouldn't be wary of dropping
           | such inaccuracies, especially when they bring such strong
           | connotations.
        
             | PaulHoule wrote:
             | For one thing the technology in an MRI based on a
             | phenomenon known as nuclear magnetic resonance
             | 
             | https://en.wikipedia.org/wiki/Nuclear_magnetic_resonance
             | 
             | they dropped the "nuclear" bit because it is scary, it
             | doesn't involve any ionizing radiation. It is all about
             | making the nucleus wobble but not about splitting atoms. I
             | have fond memories of doing NMR experiments in senior labs
             | as a physics major.
        
           | alyandon wrote:
           | I'm not one to typically have strong fear/anxiety responses
           | in situations that aren't actually dangerous. However, I felt
           | extremely uncomfortable being partially inserted into an MRI
           | tube for a lower body scan. I couldn't imagine being shoved
           | head first into that thing without being heavily sedated or
           | completely knocked out.
        
             | kstrauser wrote:
             | I had a head MRI and my main anxiety involved praying to
             | any powers that be that my tooth crown was truly non
             | magnetic.
        
               | Loughla wrote:
               | Sweet Lord, that is a white hot fear. When you remember
               | the really old metal filling you have right before the
               | machine kicks on.
        
               | kstrauser wrote:
               | The thought crossed my mind, to be sure! I talked about
               | all that with the techs beforehand. "Are you _sure_ this
               | isn 't going to yank my teeth out?" "Pretty sure. Now
               | stop moving around."
        
               | TeMPOraL wrote:
               | They put metal detectors even in schools these days,
               | can't they put one before the MRI lab?
        
               | lawlessone wrote:
               | I have permanent braces attached to the back of my teeth.
               | I know they're magnetic, i can feel a slight pull if i
               | hold a magnet close to them.
               | 
               | I don't know what i'll do if i ever need an MRI,
               | otherwise i'd probably just find it cozy..
        
               | kstrauser wrote:
               | I have a simple hiatal hernia. One of the treatment
               | options is to basically put a weighted band around your
               | esophagus above the stomach so that the weight holds
               | everything downward so your stomach doesn't get pulled up
               | through the hernia. I imagined being in a car accident or
               | some other situation where I'm nonresponsive, the doctor
               | ordering an MRI, and me re-enacting the scene from Alien.
               | Nah, I'll take my chances with the hernia, thanks.
        
             | kedihacker wrote:
             | I feel uncomfortable around x-ray rooms. Can humans feel
             | radiation or I am making it up?
        
               | MichaelDickens wrote:
               | Humans cannot feel x-rays in the dosages you'd experience
               | in an x-ray room. A sufficiently powerful x-ray would
               | feel hot the same way a bright light does.
        
               | ballenf wrote:
               | The mandatory shielding around these rooms is robust. I
               | shadowed a technician inspecting a newly fitted x-ray
               | room and observed the very sensitive equipment used to
               | verify absence of leakage. There was a small puncture in
               | the lead shielding that was quickly found and resulted in
               | a delay until patched.
               | 
               | I don't know what you mean by "around" but if you mean
               | walking down the hallway outside the x-ray room, my guess
               | it's the low frequency sound these machines often produce
               | that you're reacting to and not x-rays themselves. Not to
               | mention the almost sci-fi signage alerting your brain to
               | danger.
               | 
               | And inside the shielding envelope, modern x-ray equipment
               | is still at very low levels unless you're the patient
               | (and even as the patient, imaging requires much lower
               | levels than in the past).
        
               | DocTomoe wrote:
               | Could be a million things you subconsciously notice.
               | 
               | * the warning signage
               | 
               | * things that are related to the lead shielding (micro
               | changes in gravity, smell of lead salts, ...)
               | 
               | * infrasound caused by the machinery
               | 
               | * people waiting for an x-ray around who are less-than-
               | happy...
               | 
               | The problem with this kind of thing is that it is often
               | highly individual, and barely, if all measurable with our
               | current scientific instruments. Some people keep claiming
               | that humans are incapable of even hearing infrasound, or
               | sense gravity, claiming anyone who _can_ sense them is
               | spreading new-age esoteric nonsense or is mentally ill.
               | See also: Electrosensitivity.
               | 
               | I'm not saying these things do or do not exist, just that
               | it is in the realm of possibility.
        
               | lawlessone wrote:
               | Does it make break down oxygen into ozone ? If it does
               | maybe some people smell it
        
               | PaulHoule wrote:
               | I wouldn't worry much as an X-ray recipient. There was
               | talk in the 1950s about the trade off of getting a
               | routine chest X-ray, say to check if you have pneumonia
               | if you see your doc about a respiratory infection, vs a
               | hypothetical risk of cancer.
               | 
               | Today X-ray dosages are way less because they use
               | 
               | https://en.wikipedia.org/wiki/Digital_radiography
               | 
               | so I wouldn't be afraid to get one. The radiology
               | technician though needs to take special precautions
               | because they are around it all day. Personally I would
               | avoid a CAT scan if it were feasible
               | 
               | https://en.wikipedia.org/wiki/CT_scan#Adverse_effects
        
               | 01100011 wrote:
               | Nah, energy is way too low. If they emitted enough for
               | you to feel it you'd be dead in a week.
               | 
               | I certainly felt my last MRI though. New machine, so
               | probably high powered. Abdominal/liver MRI. Every time
               | the RF was on I could feel a gentle warmth throughout my
               | midsection. Weird but cool.
        
             | PaulHoule wrote:
             | I don't really mind medical procedures like that. The time
             | I got punched at Elephant Butte Lake and got stitches at
             | the emergency room I went into a deeply relaxed state that
             | scared the nurse because she thought I'd fallen asleep.
             | Even the noise of an MRI machine is not that startling if
             | you know it is coming.
        
               | rjbwork wrote:
               | Indeed. I have a brain tumor (not cancerous and
               | controlled by medication) and for a few years after
               | diagnosis I had to get MRI's every few months for the
               | first year, then one every year for a few years. It was a
               | bit nerve wracking the first couple times but now I can
               | fall asleep in those machines lol.
        
             | frereubu wrote:
             | During my MSc I spent a total of more than 25 hours being
             | scanned in an MRI machine for a study investigating the
             | neurobiology of reading, and by the end of the study I was
             | so relaxed in there that my main problem was not falling
             | asleep because I was lying down with repetitive noises
             | around me!
        
           | dv_dt wrote:
           | So this activity pattern could actually be the
           | _claustrophobia mode network_?
        
             | TeMPOraL wrote:
             | Or "questioning the life decisions that led to finding
             | myself in this situation" mode network?
        
         | a_c wrote:
         | There is no grand design in biology. If something ain't broke,
         | evolution ain't going to fix it. Retina in mammals facing
         | backwards that gives rise to blind spot is one example. The
         | laryngeal nerve that goes all the way down aorta and back up
         | the neck is another
        
           | jjk166 wrote:
           | Eh evolution will certainly try to fix things that ain't
           | broke, indeed it will try to vary just about everything at
           | some point or another. Bad cable management remains because
           | no one survives the intermediate steps between functional
           | configuration A and optimal configuration Z.
        
           | Iolaum wrote:
           | Not exactly. Everything in our body needs energy to maintain
           | itself. It has to provide some value for the energy it
           | consumes, otherwise not having it becomes an evolutionary
           | advantage meaning evolution will gravitate towards it.
        
             | duskwuff wrote:
             | What a_c is getting at is that evolution can become trapped
             | in local optima. The backwards retina in mammals is
             | suboptimal, but it's locally optimal - the path from where
             | we are to a better design (like the one in squid) is too
             | long for evolution to hill-climb up to.
        
           | Noumenon72 wrote:
           | Informative X thread on how the recurrent laryngeal nerve
           | path is dictated by having to develop embryos through
           | chemotaxis:
           | https://x.com/culpable_mink/status/1850937701518000383
           | 
           | He mentions that even if you're a giraffe, you have nerves
           | just as long running to the end of your spine, and from your
           | spint to the bottoms of your feet, so the extra length of
           | nerve isn't really a problem.
        
             | a_c wrote:
             | There is a pathway for every possible configuration. It
             | doesn't dictate whether a configuration is optimal. Maybe
             | the laryngeal nerve isn't that bad. But that doesn't
             | guarantee all anatomy and physiology optimal
        
           | pfdietz wrote:
           | Also, if something truly serves no purpose, evolution will
           | allow it to go away.
           | 
           | The classic example is the enzyme needed to make vitamin C.
           | In our primate ancestors that lived on a diet rich in vitamin
           | C, there was no penalty to losing this enzyme. Mutations that
           | destroyed its function were not selected against. As a
           | result, we now can't make vitamin C; the remnants of the gene
           | for the enzyme have been so damaged that there's no path back
           | to the working version.
        
         | EvanAnderson wrote:
         | On the theme: The phrase "junk" DNA always irritated me. I'm
         | glad it is being replaced with "non-coding".
         | 
         | Anybody who has looked at a 4kb demo can intuit that "junk"
         | code likely has a function, even if it isn't immediately
         | obvious machine code for the host CPU. I'm no geneticist, and I
         | understand cells aren't CPUs, but I've read enough to know
         | there's at least a tenuous analogy to non-coding DNA and the
         | kind of "junk" you might find reversing a 4kb demo that
         | procedurally generates its output.
        
           | TeMPOraL wrote:
           | Yup, DNA turned out to not _merely_ be a sequence of triplets
           | telling a dumb matter printer which hard-coded proteins to
           | make - at least according to what little I understand of
           | evolutionary developmental biology[0], DNA is _much_ more
           | like procedural generation in gamedev or demoscene. That is,
           | there 's plenty of _recipes_ for various structures and body
           | parts, and then there 's lots of DNA that's responsible for
           | conditionally enabling or disabling or modulating those
           | recipes, depending on more DNA that controls _when_ and
           | _where_ and _how much_ to enable them, and then more - a
           | complex network of _logic_.
           | 
           | --
           | 
           | [0] - Didn't get much further than this four-minute intro to
           | the field, but _it is a good intro_ :
           | https://youtu.be/ydqReeTV_vk.
           | 
           | (EDIT: It's actually the second part of a trio, that starts
           | with a four-minute bottom-up overview of organic
           | chemistry[1], and ends on a three-minute intro to
           | nanotechnology[2]. I recommend the series together for how
           | well it frames humans in relation to other life and universe
           | as a whole.)
           | 
           | [1] - https://www.youtube.com/watch?v=f8FAJXPBdOg
           | 
           | [2] - https://www.youtube.com/watch?v=ObvxPSQNMGc
        
             | throwup238 wrote:
             | There's also epigenetics with mechanisms like histone
             | modification and DNA methylation that can control
             | expression without changing the DNA, but still being
             | heritable.
        
               | mapt wrote:
               | There are something like (in the reference diagram I'm
               | looking at) eight levels of organization in the structure
               | 'chromosome': https://en.wikipedia.org/wiki/Chromatin#/me
               | dia/File:Chromati...
               | 
               | Only the first one is DNA, and only a small portion of
               | 'coding' DNA was initially regarded as important.
               | 
               | My question is how? Structural organization implies
               | information. Who thought "Nah, evolution put that in for
               | shits and giggles"? Was it just things we couldn't
               | observe at all without modern scanning electron
               | micrography?
        
               | adgjlsfhk1 wrote:
               | so the thing that makes this complicated is that having
               | non-coding DNA that does nothing for an individual can
               | still be helpful for a population. they essentially serve
               | the same purpose as commented out code that is really
               | common when devs aren't using version control. the
               | comments won't affect the program as it currently exists
               | at all, but they make it so small changes to the code can
               | more easily change the functionality.
        
               | TeMPOraL wrote:
               | Maybe not as much commented as _unused_. Turns out, there
               | 's plenty of that in DNA, and you can force turning it
               | on. See e.g. the bit about snakes growing legs in the
               | video I linked - they still carry the blueprint for legs
               | in their genome, but have it suppressed.
        
               | TeMPOraL wrote:
               | > _Was it just things we couldn 't observe at all without
               | modern scanning electron micrography?_
               | 
               | Perhaps also that we couldn't imagine, much less accept,
               | that a dumb semi-random process tweaking bits could, over
               | time, organize those bits into higher level _abstract_
               | structures. We still mostly talk about evolution mutating
               | genes, where perhaps if you zoom out a little, it 's
               | actually working at a higher level of abstraction.
               | 
               | Incidentally, this is the same outlook as some people
               | have today wrt. LLMs - they can't accept the idea that
               | backprop running on a blob of weights representing a
               | simple (if large) graph can start encoding increasingly
               | high-level, abstract organizational structures.
        
               | wbl wrote:
               | Can't observe and woefully hard to understand. Remember
               | in the 1950's the only genetic disease they could trace
               | to a mutation was sickle cell and that was guesswork.
               | They didn't have any of the cute editing techniques or
               | amplification and sequencing tools. It's a miracle they
               | figured out what they did.
        
               | PaulHoule wrote:
               | More to the point, there is still chromosome structure
               | when the cell is normal mode, expressing proteins instead
               | of replicating itself. It's just it is spread apart,
               | probably like a pop-up book where "pages" will snap open
               | and become accessible for transcription as part of gene
               | regulation and other times will be folded up so genes in
               | that section aren't expressed.
               | 
               | Some of the reason it is tough to make GMO products that
               | are really effective is that it's not enough to put a
               | gene in and have it expressed a little, you want to have
               | it expressed a lot. For instance the first version of
               | _Golden Rice_ produced Vitamin A but not enough to
               | matter, it took several years to make one that expressed
               | the genes strongly enough that it made significant
               | amounts of Vitamin A.
        
           | 725686 wrote:
           | You might enjoy the book Junk DNA by Nessa Carey. Very
           | interesting how complex and interrelated our DNA is. Pretty
           | much spaghetti code.
        
         | marliechiller wrote:
         | Tonsils are a good example of this. New studies are finding
         | that they may be part of the immune system. Anecdotally, I had
         | mine removed as a child due to frequent tonsilitis. As an
         | adult, I suffer from a number of airborne allergies. Most
         | likely a coincidence, but it does make me wonder!
        
         | ajb wrote:
         | A lot of this comes from the assumption that our organs each
         | have a single purpose, so if the obvious purpose is not
         | relevant in humans then the organ is useless. But most organs
         | serve multiple purposes.
        
         | s_dev wrote:
         | The Chesterton's Fence of body parts.
         | 
         | https://en.wikipedia.org/wiki/G._K._Chesterton
        
           | Damogran6 wrote:
           | Man, does THAT sum up the current political climate in
           | America.
           | 
           | There exists in such a case a certain institution or law; let
           | us say, for the sake of simplicity, a fence or gate erected
           | across a road. The more modern type of reformer goes gaily up
           | to it and says, "I don't see the use of this; let us clear it
           | away." To which the more intelligent type of reformer will do
           | well to answer: "If you don't see the use of it, I certainly
           | won't let you clear it away. Go away and think. Then, when
           | you can come back and tell me that you do see the use of it,
           | I may allow you to destroy it."[97]
        
             | MrPatan wrote:
             | The Chesterton fence defense (yeah!) doesn't apply.
             | 
             | Did you care about Chesterton when the previous set of
             | fence-smashers went around smashing (much older) fences?
        
               | estebank wrote:
               | The Chesterton fence argument is that you need to
               | understand why the fence is there. If you _do_ understand
               | it, and still remove it, it doesn 't say that's bad.
        
         | card_zero wrote:
         | No matter how hard I twiddle the left nipple, I can't seem to
         | pick up Jazz FM.
        
           | yread wrote:
           | My grandfather managed to persuade me when I was 4 that beer
           | comes out of man's nipples. Unfortunately, at the time he was
           | supposedly too old for it to happen. And my father was too
           | young. So, I've never seen it in action
        
         | andrewl wrote:
         | Agreed. There is, or at least were, some parts of the body that
         | were only recently _discovered_ and not just known about and
         | assumed to be inactive. It was only in 2015 that lymphatic
         | vessels were discovered in the central nervous system:
         | 
         | https://www.nih.gov/news-events/nih-research-matters/lymphat...
         | 
         | That article is about mice, but they were later found in
         | humans, too.
        
         | adolph wrote:
         | Epistemological modesty/honesty is undervalued compared to
         | confident certainty (in my mind at least).
        
         | pc86 wrote:
         | I would expect at least _some_ evolutionary pressure to get rid
         | of unused things in your body. Let 's just take the appendix as
         | an example because it's probably the most common "you don't
         | actually need this" thing that people know about.
         | 
         | Some appendixes burst. Sometimes this kills people. Sometimes
         | this happens before that person has been able to reproduce.
         | Wouldn't this cause selection for people who at the very least
         | don't have bursting appendixes (appendices just sounds wrong to
         | my inner narrator in this context), but also for people who
         | have smaller ones. Over time this pressure would decrease but
         | shouldn't it theoretically over many many generations result in
         | smaller and smaller, eventually disappearing, appendixes?
        
           | grog454 wrote:
           | I would think so. Who says that's not happening now? It seems
           | reasonable that evolutionary pressure can be strong enough to
           | have a significant impact in 1-2 generations (for example due
           | to the introduction of a new environmental threat) or weak
           | enough to take thousands of generations.
        
           | kjkjadksj wrote:
           | Appendix is being appreciated these days as a reservoir of
           | good gut bacteria. So there's actually probably some pressure
           | to keep it around. Appendicitis is a thing but of course not
           | everyone suffers it. Maybe in the primitive world you were
           | more likely to see your skull meet a rock before that
           | happened in significant numbers of people in the population
           | to the point it affected offspring counts.
        
           | 4gotunameagain wrote:
           | Can we be sure that we don't need the appendix ?
           | 
           | We used to think tonsils are optional as well, and there seem
           | to have been some studies that find a link between
           | tonsillectomy & Crohn's, Hodgkin's or even breast cancer
           | (from wikipedia).
           | 
           | There surely must be vestigial parts in our organisms, like
           | the one in the article, but more often than not we have no
           | fucking clue how they interconnect with the whole and what
           | their function is.
           | 
           | I think. I'm not a doctor or anything.
        
           | evertedsphere wrote:
           | for me, appendix / appendixes (organ) / appendices (to a
           | book) too, just like index / indexes (database) / indices
        
           | sixo wrote:
           | Whether a thing can be selected-out depends on the shape of
           | the fitness landscape in the environment.
           | 
           | For example, appendix-bursts are clearly rare enough and
           | treatable-enough that they cannot be selected-out in modern
           | humans. (But almost nothing can if almost everyone is able to
           | reproduce, and any selection effects will be driven by the
           | _number_ of children which is largely cultural.)
           | 
           | If a thing hasn't been selected out, you can roughly conclude
           | either that:
           | 
           | 1. The selection pressure to do so isn't strong. Either few
           | appendix bursts occur in an ancestral env, or they don't
           | disrupt reproduction bc they happen later in life, or are
           | treatable, or other causes of death kick in before the
           | appendix matters.
           | 
           | 2. Or, if the selection pressure is strong, there is "nowhere
           | to go" in gene-space that improves this aspect of fitness,
           | within the search-radius. (Which is really equivalent to 1:
           | the selection pressure isn't strong _enough_ to search widely
           | enough)
           | 
           | 3. Or there is a stronger selection pressure _for_ it, even
           | if you can 't figure out what it is, like the "backup gut
           | bacteria" thing for the appendix. (Which is actually
           | equivalent to 1/2 also: the selection pressure isn't strong
           | enough to find a way to separate the upside from the
           | downside)
        
         | arijo wrote:
         | Take mitochondria as an example.
         | 
         | There has been a revolution in the understanding how this
         | organelle works in the last few years.
         | 
         | https://www.sciencedirect.com/science/article/pii/S089865682...
        
         | ndr wrote:
         | Evolution works on a different timescale than what science
         | divulgation headlines, and selected lineages to care about how
         | to cross deadly valleys even though they might have appeared
         | rarely. There's little room for baggage.
        
       | desibanda wrote:
       | I know how to look hard by squinting my eyes and trying to focus,
       | talk hard by speaking as loudly as I can or smell hard by
       | breathing in as much as I can, but how do you listen hard?
        
         | mkoubaa wrote:
         | Try explaining in words how to raise a single eyebrow to
         | someone who can't.
         | 
         | Tactile intelligence and semantic intelligence do not overlap
        
           | HelloMcFly wrote:
           | I've gotten at least two people (youths) to be able to raise
           | a single eyebrow by placing their finger on their eyebrows
           | and feeling their muscles activate as they raise and lower
           | both eyebrows. Keeping your fingers on the eyebrow muscles,
           | it's almost like your brain can start to "see" the two
           | distinct muscles. It didn't take them too long (days not
           | weeks, not hours) to be able to raise an eyebrow.
           | 
           | There's probably a biological component to it to, I'm not
           | saying this will work for everyone because it didn't work for
           | my spouse.
        
             | mkoubaa wrote:
             | Part of the teaching was physical. Hard to do it with words
             | alone
        
       | philipwhiuk wrote:
       | Quiet batpeople.
        
       | blarg1 wrote:
       | My ears tire when hearing foreign languages spoken, it feels like
       | my ears keep automatically trying to discern each word as if I
       | might understand them.
        
         | kennyadam wrote:
         | Stapedius-mediated phonemic saturation is almost unheard of by
         | most people.
        
       | EvanAnderson wrote:
       | There's money here to whoever can capture the activation of these
       | muscles to control prosthetic cat ears. At the rate I see them
       | the prosthetic cat ear market must be double-digit billions.
       | 
       | Seriously, though, it makes me wonder if the activation of these
       | muscles could be used in a hearing aid application. Why not add a
       | couple rear-facing highly directional mics and use these muscles
       | to control their gain?
        
       | hyperbovine wrote:
       | I have this weird muscle in my ears I can flex to block out (or
       | at least lessen) loud noises. I've never been able to explain it
       | adequately to anyone, or find out what is going on, but it's
       | absolutely real and not just, wait for it, .. in my head :-)
        
         | fumar wrote:
         | If I do that, I hear a rumbling. I never used it to block out
         | sound.
        
           | mimentum wrote:
           | Same. Wonder how common this is.
        
           | Tor3 wrote:
           | Same here, I hear a rumbling. I do occasionally use this to
           | block or lower very loud (potentially hearing-damaging)
           | sounds if there are no other means available.
        
           | wkjagt wrote:
           | I can do the rumbling too. And a clicking too. I can even
           | make someone else hear my ear clicking by having them press
           | their ear to mine. I wonder if that's causes by the same
           | thing.
        
             | NitpickLawyer wrote:
             | > And a clicking too.
             | 
             | You should get a check-up, when I heard clicking I had some
             | wax accumulation.
        
           | hinkley wrote:
           | According to the Wikipedia article it may be involuntary.
        
         | gorlilla wrote:
         | I tried explaining this to my wife and she thought I was crazy.
         | Turns out she was right, but not for this reason.
        
         | dguo wrote:
         | I can do the same and also didn't know how to explain it until
         | I stumbled upon this subreddit:
         | https://www.reddit.com/r/earrumblersassemble/
         | 
         | So apparently we can control our tensor tympani muscle:
         | https://en.wikipedia.org/wiki/Tensor_tympani_muscle
        
         | krisoft wrote:
         | That's absolutely real. It sounds like you are describing the
         | Tensor tympani muscle.
         | https://en.wikipedia.org/wiki/Tensor_tympani_muscle
         | 
         | In modern cars when the vehicle detects an impending collision
         | it floods the cabin with pink noise to trigger a reflexive
         | contraction of this muscle to protect the passenger's hearing
         | from the even louder sounds of the collision and the airbags.
         | 
         | https://spectrum.ieee.org/pink-noise-says-prepare-for-impact
        
         | albrewer wrote:
         | Sounds like you might have conscious control over your tensor
         | tympani muscle[0].
         | 
         | [0]: https://en.wikipedia.org/wiki/Tensor_tympani_muscle
        
       | teeray wrote:
       | There's muscles in my ears that I have conscious control of that
       | don't really seem to do anything other than make a rumbling
       | sound. They were fun to use when I was young playing, since I
       | could make explosion sounds and get a realistic rumbling bass
       | too. Are these the same muscles?
        
         | jrmg wrote:
         | Seems like not:
         | 
         | https://en.wikipedia.org/wiki/Tensor_tympani_muscle
         | 
         | I can do this too. The article mentions it being "rare", but it
         | sounds like it hasn't really been studied so might actually be
         | common. From casual discussion with friends in the past I
         | suspect it's more like 30-50% of people.
        
           | xg15 wrote:
           | Same here and I always sort of assumed this was a normal
           | thing of the human body. I'm kinda shocked to learn that many
           | people _can 't_ do it.
           | 
           | What kind of muscle can switch between voluntary or
           | involuntary depending on the person?
        
           | fluoridation wrote:
           | Oh, so that's what that is? Crazy. Subjectively (besides the
           | sound) it just felt like a vague pressure in my head, near
           | the neck, so I never could figure out what the hell it was I
           | was doing.
        
           | anotherevan wrote:
           | As the article mentions, the tensor tympani muscles are also
           | involved in hyperacusis, which is an inability to tolerate
           | sound at volumes most people have no issue with.
           | 
           | One of my kids has this. The best analogy I've found is it is
           | like standing out in the sun when you already have sunburn.
        
         | _fs wrote:
         | https://www.reddit.com/r/earrumblersassemble/
        
         | hinkley wrote:
         | I do this sometimes when my ears are congested and I'm trying
         | not to do weird things with my jaw where people can see, to
         | open up my Eustachian tubes. It works about a third of the
         | time.
        
       | buildsjets wrote:
       | Most people may not use these muscles, but I do, to adjust the
       | focus of my bifocals as needed. Zoom and enhance!
        
         | alexjm wrote:
         | That was how I learned to tense my ear muscles -- because I
         | could see they made my glasses shift on my face.
        
       | otikik wrote:
       | I ... thought this was common knowledge.
       | 
       | I learnt how to wiggle my ears when I got startled by a book
       | falling from a shelf and my ears instinctively "raised". Picture
       | a dog going from "idling" to "alert", with the ears pointing up.
       | It was like that, but for humans.
       | 
       | I then said "Ooooh, so that's how you do it".
       | 
       | There has never been a doubt in my mind that the muscle is
       | connected to "alert, listen closely".
        
       | tim333 wrote:
       | There's a lot of odd stuff we're gradually figuring. Also
       | interesting, some of the hair cells in the ear act as amplifiers
       | and you can hook them up to an electrical sound signal and have
       | them dance around:
       | 
       | https://youtu.be/pij8a8aNpWQ
       | 
       | I suspect the standard explanation for that as given under the
       | youtube video:
       | 
       | > Since the amplitude, and hence the mechanical energy, of
       | airborne sounds is tiny, the cochlea mechanically amplifies the
       | incoming vibrations.
       | 
       | is wrong as it doesn't really make sense from an engineering
       | point of view - if you've already detected the sound to activate
       | the hair cell then that job's done. My theory is they actively
       | damp down the large vibrations so you can pick up the small ones.
       | There's a 10^5 amplitude difference between large and small.
        
         | TeMPOraL wrote:
         | > _the cochlea mechanically amplifies the incoming vibrations_
         | 
         | Is that even possible in principle? Amplifying requires adding
         | energy, it has to be either provided from somewhere else or
         | redistributed from other parts of the input.
         | 
         | EDIT:
         | 
         | Aha, but apparently this system is not a _passive_ amplifier at
         | all! Per Wikipedia[0], this is an active, _electromechanical_
         | amplifier, which makes the explanation you quoted more
         | reasonable (if not accurate).
         | 
         | --
         | 
         | [0] - https://en.wikipedia.org/wiki/Cochlear_amplifier but the
         | core observation is also stated in summary here[1].
         | 
         | [1] -
         | https://en.wikipedia.org/wiki/Organ_of_Corti#Cochlear_amplif...
        
           | philomath_mn wrote:
           | Idk man, survival seems like a pretty blunt selection force
           | for such an intricate mechanism
        
       | Ylpertnodi wrote:
       | The angle you tilt your head to, to REALLY listen intently is
       | known as "Mozart's Incline". Honest.
        
       | Tool_of_Society wrote:
       | Am I the only one that consciously uses that muscle??
        
         | yrcyrc wrote:
         | Nope. Came here to find such relating experiences and only
         | found yours.
        
         | bmicraft wrote:
         | Very useful with anc in-ear headphones in if I want to listen
         | for something quickly.
        
       | kazinator wrote:
       | This is not news. People know this. I can move my ears
       | voluntarily, and when I'm trying to listen, I can feel that
       | happening. It's probably half conscious. There is an intuitive
       | purpose behind these muscles, which is to do the best impression
       | of pricking up your ears that some evolutionary predecessor was
       | able to do better.
        
       | pazimzadeh wrote:
       | "Huh, we cut through that muscle every day"
       | 
       | -ear nose and throat surgeon
        
       | orangepenguin wrote:
       | I think there's a big difference between "activating" a muscle
       | and "getting utility" out of it. Sure, maybe it activates
       | sometimes, but what does it _do_? Well... nothing. It 's a
       | vestigial structure.
        
       | hackernj wrote:
       | I can't move my ears at all. My wife can do the following: raise
       | either eyebrow; move either ear back and forth; move either ear
       | up and down; twitch the upper left lip, or the upper right lip,
       | or the lower left lip, ...; and twitch either nostril.
        
       | moi2388 wrote:
       | Today I learnt some people can't move their ears, eyebrows or
       | nostrils.
        
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