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Man can change his pupil size on command

livescience.com

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Re: Man can change his pupil size on command

#121

Post by SomeHacker44 »

uj8efdkjfdshf wrote: post #104
monitron wrote: post #99

Earlier quoted context omitted.

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)

Re: Man can change his pupil size on command

#123

Post by cryptica »

hnthrowaway8251 wrote: post #43

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.

Re: Man can change his pupil size on command

#124

Post by danjc »

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).

Re: Man can change his pupil size on command

#125

Post by _tom_ »

tsimionescu wrote: post #20

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 i…

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.

Re: Man can change his pupil size on command

#126

Post by sethammons »

spoonjim wrote: post #116
msdrigg wrote: post #66

Earlier quoted context omitted.

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.

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.

Re: Man can change his pupil size on command

#127

Post by h2odragon »

Kinrany wrote: post #74
h2odragon wrote: post #52

"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.

Re: Man can change his pupil size on command

#128

Post by pjerem »

dec0dedab0de wrote: post #90
SamBam wrote: post #85

Earlier quoted context omitted.

> 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 tim…

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 s…

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

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

Re: Man can change his pupil size on command

#129

Post by xupybd »

monitron wrote: post #57
justinclift wrote: post #46

Earlier quoted context omitted.

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.

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.

Re: Man can change his pupil size on command

#130

Post by sethammons »

Sohcahtoa82 wrote: post #118
Cthulhu_ wrote: post #39

Earlier quoted context omitted.

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.
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