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Man can change his pupil size on command (livescience.com)
195 points by samizdis on Sept 1, 2021 | hide | past | favorite | 150 comments



If you're not down to read garbled blogspam, here's the actual paper: https://www.sciencedirect.com/science/article/pii/S016787602...


A quick search online brings up multiple articles dating back a few years with examples of the same thing. It's not "an impossible feat".

https://www.bbc.com/future/article/20160229-the-sea-nomad-ch...


The headline is not acuratly representing the contents of the article. The full quote which is where the "once thought an impossible feat" part comes from:

> That makes D.W. different from other people who have demonstrated the ability to change their pupil size, Strauch told Live Science. What's more, that he can feel the muscles in the pupils directly "is astonishing, as it was thought to be impossible."

What's new isn't controlling the pupils but to "feel the muscles directly". Not sure how that part is verified though.


Yeah. I've been able to do this for years. Not immediately, but with some concentration and focus when standing in front of a mirror. Works probably 75-80% of the time.

So, "impossible feat"... how would they even think that?


If it takes time and is not wholly reliable, it sounds like you might be using one of the "indirect methods" they mentioned in the article.


I can change the focal point of my eyes on command to a far away point or a close one, and I have noticed that this reliably makes my pupil get slightly larger or smaller.


That's neat. I wonder if the pupil is actually changing size, or if it's the changing shape of the lens that is making it appear so. If you look into a camera lens as the focus is changed, the inner parts of the camera do appear to change size.


It's the accommodation reflex [0] at work here - pupillary constriction goes hand in hand with a shortening of the focal length of the lens, and the eyes also converge together. This is a brainstem level response, so I doubt there'd be any easy way to dissociate these movements consciously.

[0] https://en.wikipedia.org/wiki/Accommodation_reflex


Interesting, this makes sense. Thanks for figuring it out


The eye's lens is behind the iris (unlike a camera which is typically the other way around), so the optics shouldn't affect the apparent pupil size.


Whoa. I had no idea. Thanks for informing me! That's so weird. I had always assumed that the curved front surface of the eye was the lens.


You're not wrong - the cornea (front of the eye) has about 3x the refractive power of the lens. Both function as converging lenses, and the only difference is that the refractive power of the lens can be changed.


...until age 45 to 50ish, when the lens hardens into a focus close to infinity and you start to need reading glasses. (presbyopia)


I recently discovered / figured this out as well, while practicing meditation. I have found it's a great way to relax my eyes periodically while staring at a screen.

Still can't move my eyebrows independently though.


Yeah, the article mentions that as the early way the man learned to do it, before being able to directly control the muscle.


This guy can “tremble” his pupil. It’s not the same at all.


I knew a dozen kids in middle school who would do that. I got to the point I can do it sometimes.


It sounds similar to how I learned to move my toes independently. It's harder than you'd think and takes a lot of focus. I don't think it's indirect control.


Nope. They only thing I focus on when doing that is changing the pupil size.


Similarly, I can stop hiccups mentally. It's just a little trick of concentration while focusing on the right thing.


I hadn’t heard of this being an impossible feat before and I likewise don’t see why it would be. I remember from Kahneman’s work on human biases and fast/slow thinking that they used pupil dilation as a great proxy for how much conscious concentration someone is using. So I don’t see why controlling it would be such an impossible thing.


First line of the paper:

> Direct control of the pupillary musculature is deemed impossible (Loewenfeld, 1993).

Also, from the abstract, they tested to rule out "increases in arousal by increased mental effort". This is a different phenomenon than what you are discussing.


But it says "once thought an impossible feat". That's cromulent journalism; helps disseminate the idea that it isn't.


This was the first thing that came to mind. They show the children controlling their pupils. https://youtu.be/YIKm3Pq9U8M


And to confirm, I knew someone in school who could do this, though I was never able to do it myself despite some notable time wasted in front of the mirror.


if a hundred people on a population of 8 billion can do it, on command, at will, immediately, it's an impossible feat.

It's not the act of changing the pupil size that's the impossible feat, it's the "doing it instantly, on command" part that's the impossible feat. Even if lots of people can change their pupil size, virtually no one can with the snap of their fingers.


This reminds me of the Bene Gesserit and other schools that sprung up in Frank Herbert's Dune. Once computing technology was forbidden, these schools started research in 'human technologies', learning to control and use their own (or another's) body as a kind of machine. I do wonder if there is any possibility of actually doing things like extending conscious control over more bodily functions, if we were to try at it for a few thousand years (both directly and through selective breeding).


Another book that explores this is A Deepness In The Sky, where people can be infected with a virus that can produce neurotoxins and be directed by MRI. It is used to provide "Focus", a sort of autistic savant state where people can be turned into hyper-specialized computers, although at a higher level of abstract than normal.


> sort of autistic savant state where people can be turned into hyper-specialized computers, although at a higher level of abstract than normal.

That’s me after my Vyvanse dose kicks-in…


Biofeedback is a real thing. You can learn to control (within limits) many aspect of your body:

https://www.mayoclinic.org/tests-procedures/biofeedback/abou...

I had a professor studying using it to mitigate Reynaud's disease, https://www.mayoclinic.org/diseases-conditions/raynauds-dise..., to gain some control of circulation in the fingers.

But it's not like a movie, you aren't getting powers, but more shifting things to another point in their normal range.


Yes.

Look into practices of Tibetan monks and Indian Yogis. They specifically train their bodies to do extraordinary things.

One example is that they will meditate outside in near- or sub-freezing temperatures and have cold wet sheets placed on their skin, which they will heat and dry by controlling their metabolism (no shivering involved)[1]. I'd not be surprised to find that these studies and practices were an inspiration for Herbert's idea in Dune.

[1] https://news.harvard.edu/gazette/story/2002/04/meditation-ch...


A similar idea was in the ending of the book "The Last Cato", by Matilde Asensi.

Hypnosis is a tool that is tremendously useful for the control of vegetative functions (I am an hypnotist myself), but unfortunately it has suffered from an abundance of charlatans, like electro-medicine.

My dream is to make hypnosis available to the general public.


I didn't think this was special? I've done this in the mirrior? Not fast or anything, but it is "on demand".


Came here to say this as well, I can change mine without moving when looking in a mirror - to me it "feels" like I'm focusing my eyes on something that isn't there.


Same here. I used this to impress my friends in primary school. I couldn't find another use for it though.


I can also blur my eyes deliberately and I sometimes use it to get a better idea of the gestalt aesthetics during drawing or graphics design work.


If you're interested, the article mentions that they're looking for more people with the ability. Theres some contact email address shown near the end.


That's just a trick to find the aliens hiding in the population.


Wouldn't blinking with your third eyelids give it away though?


Appropriate username.

On topic, though, I tried it, and changing what I'm focused on doesn't change my pupil size. But maybe I wasn't going far enough? I just looked in a mirror, focused on a spec of dust on the mirror, then changed focus to the image of something behind me, and my pupils didn't change at all.


Instead of focusing like that, think about crossing your eyes but keep them in place. It is like changing the depth of focus, but different.


I've done this since my childhood and honestly thought that everybody was able to do that.


Yeah, my wife can do this too, always been one of her go-to "human party tricks"


Indeed, i can do this too. I stopped after they diverged into different sizes (one being enlarged and one being shrunk), as I became a bit worried it was perhaps dangerous. They were restored within a few minutes, though.


Same as me.

I can do that.

Usually I ask a friend to count up to 3 and then on 3 I dilate the pupils immediately.


> It was previously known that some people can change their pupil size at will, but by using indirect methods.

> For example, researchers already knew that just thinking about the sun could constrict the pupils and that thinking of a dark room or mentally calculating something could dilate them, […]

Apparently, it is about changing the pupil’s size without any physical or mental stimulus.


How would you be able to tell if they were using 'mental stimulus' or not?


It's in the abstract of the paper. They used fMRI


Ditto, I can do it as well. I can best describe it as looking at an object and shifting it in/out of focus.


Same. I always lumped it in with "can't curl my tongue" and "cilantro tastes like soap" types of genetic differences...


I've got a weird "can't do what apparently most people can do" one and have wondered if it is genetic.

I can't walk while urinating. If I've started urinating and realize that I should be standing a little bit farther forward or back or to the side I have to stop, move, and restart.

I asked once on some other forum if others have the same restriction and everyone claimed they can easily walk while urinating.


try peeing your pants - just a little and where there won't be serious repercussions. it kind of illuminates the line between the conditioned and the physical - y'know


I've always wondered what the limits of mind over matter were. Like if I practiced every day, Could I learn to move my toes individually or with more dexterity? Could I focus on that random muscle that twitches in my leg and get it to stop, or move it myself?


When someone asks me to teach them how to play drums, I spin my fingers in opposite directions, and tell them that its their first lesson. Someone told me it was impossible in 7th grade, and I spent the next 3 days fixated on it until I could do it. I match it with drums because every step in drums is about having your body to do things your brain doesn't want it to, especially in the beginning.

I like to think of things like yoga, meditation, and prayer as a messy abstraction layer for controlling the parts of your body you normally can not. Created over millenniums of black-box reverse engineering by people of different levels of skill and honesty who are not sharing their results. One of the things guided meditation, and hypnotists will do is have you purposely relax each muscle group one at a time. Though for a specific twitch, that really depends on what is causing it.

I wish there was more skeptical, but open minded research into ancient practices. It seems it's all either people who blindly believe in their flavor of magic, or people who go in assuming it's nonsense and miss the step between the action and the result.

To put it more succinctly, mind over matter is enough of an issue that we have double blind studies to account for the placebo effect.


When learning to juggle I used a similar exercise: draw a square in the air with one hand, a triangle with the other. Another was to touch my thumb to my fingers in different patterns with each hand. Different people have wildly varying levels of difficulty with these exercises. If you find it too hard/easy just keep modifying until you find some version that is doable but hard and practice that.


> I spin my fingers in opposite directions

Trying to work out why this would be difficult, since it doesn't seem to be, so my first assumption ought to be that I'm doing this wrong.

If I point in front of me I can twirl my pointers in a circle such that they go in opposite directions. This seems to be the most intuitive and trivial, because both are actually doing the same movement (inward and outward at the same time). I can also twirl them so they spin in the same direction, this seems only slightly more difficult, but if I just think of them as tracing the wheels of car it's trivial.

Then again, I've never had any trouble patting my head and rubbing my stomach either.


Imagine there is a wheel in-front of your chest, in the same orientation the front wheel of a bike would be if you were riding it, but smaller and up higher.

Then point your index fingers toward each other so that they are both tracing the same wheel. They can each go forward or backward. Most people struggle with making them go opposite directions. To the point that they'll do it once or a half of a time, and then switch directions with one hand and not even realize it. It's fun to teach kids.

You can do it with your whole hand, or arm, or just the fingers, with different size circles, each takes a bit of practice once you get over the initial hurdle.


Wow this is the most bizarre thing...

If I imagine the wheel over my head (as if the wheel axle was vertical), or in front of me but the axle going forwards (wheel is moving left/right), I can do the opposite circles just fine.

But if I imagine the axle going left/right as you describe, it takes extra cognitive effort. If I imagine drawing circles, I can't do it. Instead, I have to think of each axis of movement separately. In my mind, I'm not thinking "Draw circles in the air", but rather, "Move fingers forward and back, while moving arms up and down".

The end result is the same, but what's happening in my mind to get there is totally different.


This was my first time trying to explain it in text without just resorting to making a video. SamBam's reply, and yours pointed out how much different it is in the different orientations. No clue why though.

I normally just ask a group of kids "hey can you do this?" then after I explain that it's different directions, watch them laugh as they try to do it.


Thank you my wife asked if I had a problem :D

Ok … 2 days, 23 hours and 57 min of training yet.


haha, nice.

spoiler alert:

The secret for me is to realize the fingers are on the same spot at the same time twice each rotation.


To nitpick, it is not as grand as mind-over-matter, but rather conscious control of things that are normally under the control of the sympathetic or parasympathetic system. IIRC the sympathetic system is more likely to be consciously influenced. Both are vital subsystems that control things like heart rate, blood pressure, etc. that you'd rather not play too much with (although it is said that you can with deep meditation).

Your question are about different things than that, and the first one is about a different thing than the second one.

Learning to move a particular muscle you don't normally use consciously (like moving your ears or your nostrils) is indeed a matter of practice. Sometimes all it takes is getting conscious that there is a muscle there, and then you improve your feedback loop between sending a command and feeling it move.

But a muscle that uncontrollably twitches is a whole different process. For instance some muscle cramps are related to dehydration or lack of certain minerals. So the cause can be more chemical than nervous system (ie coming from the nervous system).

PS: I have no particular expertise in this area.


You can definitely improve foot dexterity. People who have lost their hands get much better through practice.


It seems like there are a lot of commenters claiming to be able to do the same thing who didn't read the abstract:

"...various indirect mechanisms possibly mediating this phenomenon were tested: accommodation, brightness, increases in arousal by increased mental effort. None of these behavioral tests could support an indirect strategy as the mode of action"


"Once thought impossible," apparently, by people who have no exposure to the individual variability of humans, no faith in self-reported anecdata, or at least no desire to consider anything less philosophically perfect than spherical friction-less cows when contemplating biology.


The difference between impossible and merely rare is important: if something is merely rare, sometimes it can be trained and stop being rare.

Individual variability doesn't make people fly. It's reasonable to think there are things no one can do.


It's completely reasonable to think that no one can fly. But then we nibble at that, cuz we want to fly; and we add caveats to the rule. it becomes "People can't fly:"

- without mechanical assistance,

- without at least a wingsuit and a tall place to jump from,

- in standard gravity,

etc. So pretty much a re-affirmation of your first point.


A friend of mine can do this. When she gets angry she makes them go back and forth while staring you down, it's fairly intimidating.

She didn't realize she was doing it until I mentioned it to her though, she said she was just focussing on different things.


Since we now know that some people can change their heart beat at will, their body temperature or their immune system response, and that it's something you can train, I don't think anybody find that very surprising. But good to know.


I don't think anyone can control their heart muscle directly, but rather through meditation calm themselves and then their heart slows down. And body temperature is not controlled by a muscle so that is probably meditative as well. No comment on the immune system part.


Huh? Meditation? It is way easier than that. You can raise heart rate almost instantaneously by imagining that you are doing a rigorous exercise. Slowing it down might be more tricky because you actually need oxygen, but pausing breath with a long slow exhale will probably do the trick.


Is there any actual differece to a muscle if you think about it and it happens?


I'd consider "controlling" something to be more direct, but that's semantics I guess.

If I heard "control heartbeat", I'd think more like breathing, where one could "hold their heart" like they "hold their breath".

If meditation lowers heartbeat and temperature, I imagine that it's "control" in the strictest sense, but I'd use "influence" or some other term if I was personally describing it.


You can actually up your heartbeat and temperature too, but you are right, it's more influencing that direct control.

A muscle is instant and precise.


Have you already felt being conscious of your breathing and feeling like being unable to let it go back to automatic control ? Well …

> one could "hold their heart"

… now that sounds creepy.


Not all muscles have a spark plug at the tip delivering its own signal to pulse. The sinoatrial node does this in the heart, and it is a reciprocal system like a v8 engine where one side firing begets the other side firing next. When these signals to fire go out of whack, you get fibril movement, which is when a defibrillator is deployed, it shocks the SA node forcing a 'reboot' of sorts and if all goes well, normal sinus rhythm resumes.


I can, but it isn't 100% control. It's like putting a (voluntary) damper on an (involuntary) pendulum.


The video which you all came for is here: https://osf.io/6amrp/


I have Adie’s pupil where one pupil is abnormally dilated (mostly in indoor light for me). A little disconcerting that one of the signs of brain damage is different dilation of your pupils so if I’m ever in an accident or something I hope that’s not going to be a problem.

I’d love to be able to control pupil dilation voluntarily as I know people notice it in meetings, etc (esp in-person before covid).


I am not sure how ground breaking this is.

Pupils accommodate. Focusing on something far will make your pupil get larger and focusing on something near will make it get smaller.

Basically every normal person’s pupil does this. My guess is that person in the article is actually just changing focus without really thinking about it. Given that changing focus activates muscles in the eyes, you might be convinced that you are actively controlling the muscles in the eyes directly, and not through changing focus. In addition, the “finding” of this article is based entirely on the persons subjective experience.

Thus I think the professor found someone who accomodates as normal, but has a subjective sensation of controlling his pupils when he changes his focus.


Is it what the diving Monken people does? https://www.sciencealert.com/these-sea-nomad-children-can-se...


Wow! I did not know nobody could do it. I am personally more impressed by people who can move their earlobe I can't do this but I. can change my pupil size. I just somehow imagine looking farther when in front of a mirror.


When I was first figuring out how to move my ears as a kid it was all one motion with moving my scalp. I just thought it felt neat, and I was doing it all the time. Then I did it while getting a haircut and the lady freaked out because my hair was just moving back and forth, she made me do it for all the employees.

I later figured out how to just move the ears, and would try to control them separately, but never got that working. I feel like I just dug up a 30 year old feature request.


I never thought my my ability to move my ears as "impressive", thanks!

FWIW the muscle that surrounds the ear from behind is under direct control for me, like any other muscle. I can move the ears independently of one another.

But i sure can't raise the quizzical eyebrow over my right eye, despite being able to with my left. Funny how your nervous system can have something so dialed on one side but ghosts the other.


I believe that would be one of the "indirect methods" that's known and described in the articles as "mental effort".

Apparently the person described in the article can do it without indirect methods, and also "feel" the muscles involved.

From what's described it's almost as natural as moving an arm for them.


I just told the other half about this story and she said that she used to be able to do that.

maybe it's not that uncommon?

she's going to try again later and then email them if she can still do it


This brings us one step closer to Bene Gesserit prana-bindu nerve and muscle control

https://dunescholar.com/2020/08/28/the-bene-gesserits-nerve-...


Or Larry Niven's "A Gift From Earth" where the protagonist can make their pupils to contract and thereby cause others to lose interest in them (psi invisibility) https://en.wikipedia.org/wiki/A_Gift_from_Earth


Or Data while playing poker, although synth. https://www.youtube.com/watch?v=I9851-SsDBc


Wonder if he is just going into a lucid dream state (day dreaming) and recalling being in the pitch black (enlarging the eye's via muscle memory) or looking at the sun to contract them.

Maybe something folks could try - set your phone to selfie - think of looking at the sun/really bright light vivid memory recall event and then do the same recalling an event of your memory in which you was in the total dark (camping trip perhaps).


It says in the article that he's not doing that.


Lucid dreaming refers to dreaming while aware that you are dreaming. Day dreaming is just getting lost in one's imagination while one is awake. These are two different phenomena.


I had a friend's growing up who would do this as a trick... Didn't know it was a big deal!

I can move my nose in 4 ways and both ears independently? Does that count?



I can "tremble" my eyes, but never thought about how the pupil can be affected. I can change how I focus, too, is this common?


I can also do this. I can make my sight go blurry on demand. I didn't realize that my eyes were trembling until someone else watched me doing it and told me so.

It doesn't feel like trembling, it feels more like staring into empty space. I think that's how I discovered this trick; I was trying to train myself to stare into the void.


I can also blur my eyes and make them vibrate. But I never checked how that affects my pupils.


I am the only person I know in my group of friends who can change the focus of my eyes independently of the distance of the object I’m looking at. In other words, I can make vision go blurry (wide eyes open) without it going double.


Isn't that the mechanism for these magic images like this:

http://www.magiceye3ds.com/3dpics/img/043magiceye3d.jpg

Some people can just adjust their focus and see it immediately. Some need to put their nose through the monitor first.

edit: you should see a heart, but if you resize the image you might see something different.


That requires you crossing your eyes, or look past the image, which makes your vision double.


I can do this too, but never thought to ask if anyone else could. How rare are we talking about?


I can do it just fine. I think most people can.


I guess this doesn't bode well for that pupil-dilation test for psychopathy, huh?


I came expecting satire, reading up to the video games eye training amused, but stopped mid way confused by the level of effort going into confirming its novelty.

O’ fortuna, the things we learned in the 21st century.


You can do this, too. To dilate your pupils, defocus your eyes. Let things go as blurry as possible. To constrict again, focus on a small detail in the distance.


Thats a good start. Now he should move on to adjusting the sizes of other things on demand and start teaching it online...


This is a random tangent, but if are visually impaired and you look through a pinhole in your hand, you can see clearly!


Since sedatives dilate and stimulants constrict, I just imagine various trips Ive been on to change pupil size.


This is crazy. And meanwhile, I have trouble releasing the muscles in my neck, upper back and jaw.


I have meet a person like that before. He showed me as a party trick. Can’t be that unique.


I can also do this. I do it as eye exercises when I’m staring at screens for a long time.


"The researchers can't say for sure that D.W. was directly controlling his pupils, but from their many tests, they did not find any evidence that he was using indirect strategies."

By reading this paragraph it states that they cannot know for sure. This makes the article's title very "clickbaity" to me.


When dental assisting, it has been challenging to discover how many people have no voluntary control over their own tongues.


I have very little proprioceptive sense of my tongue, and when I'm at the dentist I have to consciously move it to know where it is. I basically pick a corner away from the dental instrument and touch the tip to that corner. After a minute or so I'll drift back to center and will hardly notice it.

I often ask the technician if my tongue is in the way, and they always say it's not, but I'm not sure I believe them. I sometimes have anxiety that if my tongue slips a little bit I'll get injured, and that sure doesn't help.

Physiologically, I would imagine that when the mouth is closed, the tactile pressure on the tongue is constant enough that your brain filters it out. When my mouth is open, the tactile pressure is gone, so there's even less sense of location. Without the muscle extension, it's just a blob of jello with no sensation. Hence why I place the tip at a specific corner.


MRI tech here: I’m surprised how many appear to have no control over their limbs. Please keep still.


I'm surprised that that group apparently also includes me. I had an awful experience during my LASIK procedure. What should've taken a few minutes ended up taking like 40+. It was almost an hour of the doctor and nurses constantly repeating "please keep still", yet from the very start to the very end I was literally making myself as still as possible and from my perspective wasn't moving any part of my body in the slightest.

It felt like some Kafkaesque nightmare, being repeatedly told to do something I was certain I was doing the whole time. And also, since it was taking so long, they had to keep restarting the whole thing over and over, including jetting my eye with freezing cold water again and again, which wasn't a pleasant sensation even with the local anesthetic. It was so confusing to me because I just... was not moving and they kept telling me to stop moving. I was neither voluntarily moving myself nor did I feel like any part of me was moving.

After it was over, they said my heart was beating so fast/forcefully that I was involuntarily moving around, or my eyes were moving around, or something. (It was years ago and I forget the exact explanation.) I know in theory one has some indirect voluntary control over their heart rate, such as with breathing patterns, but 1) during the entire procedure, they never told me that; they just kept saying "stop moving", and 2) even if they did tell me it probably wouldn't have helped much. I think the only thing that helped was my breathing eventually naturally slowed and my body started relaxing.

I had no conscious anxiety or worries going into the procedure, but I guess some part of my "lizard brain" just automatically took over once I was on the table. And probably related to this, I also have a dire case of "white coat syndrome", where the first blood pressure reading I receive at any doctor's office is often unbelievably "go-to-the-hospital-now" high, and then a few minutes later they test it again and it's normal. Again, I have literally no conscious fear of or concerns about doctors, procedures, blood pressure readings, needles, etc., but somehow my autonomic nervous system begs to differ.

So, I would guess some of the patients you work with may genuinely be just as surprised as you are when you tell them they're moving.


I've only recently started taking control of my breath (despite my parents suggesting I learn it in childhood). It is hard to imagine the impact when you're not doing it.

When you start consider that you're going to try for a minute, then three, then five. It is truly insane the amount of change you'll experience.


Can you expand a bit on this? Do you do some kind of an exercise, or just focus on how you're breathing?

Do you know why your parents suggested it?


Yes, please give a few details of how you are doing your practice.


Sure

Parents -- Its cultural. They're Indian, I'm Indian American. Square breathing and other kinds of breathwork are maybe more commonly discussed as a result.

Practice: Here's where my American-ness comes in. I've been using headspace and the Wim Hof method in the evenings and morning as well as yin yoga which is way slower than the vinyasa/cardio yoga I used to do. Sometimes I use headspace even in a lyft or during air travel

It honestly still drives me insane from time to time to be slowing down but when I (rarely still) manage to break through my frustration it changes my mood and approach.


Oh, man, that sounds like a nightmare. As someone with a lot of anxiety I was probably never going to do LASIK anyway, but after reading this there's absolutely no way I'd ever even consider it. And yes, when I find myself in an anxious situation I tend to cope with body movement, some of it I'm aware of, others probably not.


It was pretty nightmarish, but I'm still very thankful I received it. 40 minutes of awfulness in exchange for years of not needing glasses/contact lenses was worth it for me.

Also, I'm guessing this issue isn't too uncommon, because during my consultation a week or so before the procedure, they mentioned that they could give a small dose of a benzodiazepine (I think Valium) beforehand to reduce anxiety. When it was time for the procedure, I think they mentioned it again before it started but they said it didn't seem like I needed it, since I don't think I was showing outward signs of anxiety at that point, and I didn't express (or have) any conscious fears. I think there's a good chance that if I had taken it, all of the trouble could've been avoided.

So, if you make those concerns known and request one, I think you'll likely have a much better experience than I did.


My LASIK experience could not have been more opposite. I remember walking in, then putting some type of clamp to keep my eyelids from closing, you look at a red dot or a couple dots, the doctor even says you can move your eyeballs around and the laser will follow it so don’t worry about it messing up the procedure.

Then the laser activates for 10 seconds or so, you smell your burning eyeball, laser does it again to your other eye. Whole procedure is done within a couple minutes.

You get half a Xanax, go home, go to sleep, and wake up with crystal clear vision like you have never seen before.

But I also watched myself get a vasectomy, so I might not be able to relate to what an anxious person might go through.

Edit: I forgot part of the procedure. The clamp that keeps your eyelids open also slices the top layer of your eyeball and flips it open for the laser to shape your cornea. The Xanax is prob to ensure you sleep and let it heal.


> You get half a Xanax, go home, go to sleep

Wait, you get the Xanax afterwards? I'd need several Xanaxen before being able to walk into the procedure.

> I might not be able to relate to what an anxious person might go through.

Yeah, I freak out even when I get my blood pressure taken. As soon as I hear them rip the velcro on the cuff I can feel my pulse rate just about double. And then they think I have high blood pressure and I have to explain that, no, when I take it at home it's actually kind of low. Adrenalin is a heck of a drug.


On behalf of patients, we're sorry! The first time I had an MRI, my tech told me over the speaker that I was moving around too much. I was really surprised as I'd thought I was staying completely still!

I had another one more recently in which I apparently did much better. The trick for me seems to be to focus on my breathing and mental relaxation rather than trying to consciously "hold still."


> On behalf of patients, we're sorry!

I do try not to be mean - some of my kind don’t!


Don't make me contort into an awkward position inside a screaming metal disk then :(


When we run it in ‘quiet’ mode it’s so slow and the pictures aren’t as nice.

But broadly, yes.


I discovered something similar when my girlfriend cut my hair during lockdown. Apparently I can't hold my head in the same position for more than 30 seconds. It moves involuntarily no matter how hard I try to keep still.


Hint: it's easier to keep limbs still if you can rest them against some rigid part in at least 2 dimensions, and from a comfortable position of the rest of the body.

E.g. a hand is easy to keep still if it rests on a mold of a hand (doesn't even need to be the same hand as long as it matches roughly in size). This also provides a reference for the person, so they know where to keep their hand.


My new favourite is a vacuum bag thing that you out around a limb (or baby) and then suck the air out, leaving a vacuum packed person.

Comfort (pillows and blanket), sandbags, sponges, straps, tape, coaxing, as-short-as-reasonable imaging protocols and a good explanation are all standard.

It usually isn’t direct movement of the part we are scanning that’s an issue. But things like shuffling hips, stretching arms and wriggling shoulders are a problem when resolution is something like 0.25mm in plane for your foot or knee.

We can tie you down but prefer not to.


I had zero problems keeping myself still for an MRI, but I really wished I had picked a more comfortable position.

Standing still, now there I have all the problems.


I had a hard time getting my tongue out of the way when the dentist/assistant/hygienist would say it was in the way until I stopped trying to move it away from wherever it currently was to trying to move it to the opposite side of my mouth from where they were working.


When asked to move my tongue to the right or left, I have a roughly 60% success rate. Probably because you don't need to teach your tongue right and left to eat/talk successfully.


The tongue is sort of on the border. It's part of the digestive tract, which mostly works unconsciously, and when you're chewing you usually don't need to think about your tongue. Yet, you can obviously control it to an extent. People getting dental work are often nervous, and control slips a bit in that situation. I think other sorts of tics are also more common in stress situations.


I can do this too, is it supposed to be impressive?


I can do that too since I was a kid


This is crazy


Yes but can he lower or raise his cholesterol at will?


Why would you want to raise your cholesterol?


Doesn't that happen to anyone when you focus near or far?

Am I missing something?


And some can see a fappilion more colors than the rest (terrachromats), and now COVID has caused some people to lose their sense of smell.. :(

Maybe in the future we’ll have to target products and services for wildly different human hardware just as we have to do now for age, sex, computers etc.

“This product is only for people with Level 2 Eyes”


That kinda already exists though, glasses and the like. I mean it compensates for a deficiency, but still.


This comment is only available for people with Level 9000 Brains ;-)


What does it mean if I'm able to read this comment?


Then you must be over 9000


I was once asked what drugs I had taken, which confused me because I had taken none. A mirror inspection revealed that my pupils were hella dialated, for no apparent reason.

"On command" seems a plausible stretch from "spontaneously for no reason."


Hm, not really.

There are several reasons why you might have involuntarily diluted pupils, e.g. arousal, i.e. triggering a entirely natural response to a stimulus, even if it the stimulus is aehm "imaginary"/a thought (thinking about the sun).

This is called indirect control in the posted article.

Having voluntary control over your pupils is something entirely different, and just because you have dilated your pupils "by accident" doesn't mean your short of controlling them.


That doesn't seem to jive with their tests, like doing it on-demand, extending focus range beyond normal limits, or the brain activity.


In Ulm, um Ulm und um Ulm herum.

// edit This is a famous tongue twister:

https://www.ulm.de/tourismus/besucherinfos/in-ulm,-um-ulm-un...

I assumed people get the joke. And the article mentions folding the tongue.




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