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