Prince

Ok, first of all, I'm not smoking anything... I am seriously wondering, as I know very little about biology.

I was talking to my wife earlier about eyeballs, and she said that the black circle that is - as I understand it - called the "pupil", is actually a hole. I always thought it was a muscle of some kind, or a gland or whathaveyou, and that it expanded and stuff when reacting to light. Now I learn that the black circle is in fact a hole, through which the light - what we see - gets inside the eyeball, and the receptors at the other end of the eyeball "interpret" the light into an image...of sorts. Mind you, these technical terms are my words, not hers. Anyway, there's supposed to be just "eye goo" between the receptors and the pupil.

Now, here's my question. I assume that the reason the "hole", or pupil, is black, is because there is no light reflecting from inside the eyeball, so we cannot see in. Hence, my question: if it were possible to insert a needle into the eyeball and lead light into the inside of the eyeball through the needle, would a person looking at the eyeball, or specifically the pupil, see the light coming from inside the eyeball through the pupil, or would the pupil remain black?

I've included this nifty picture to demonstrate my question. See the eyeball, and then the ejection needle injecting light into the eyeball, the inside of it. Would the light then reflect outside of the pupil, making the pupil something other than just a black well of nothingness?



I ask such delightful questions. I've also wondered what the "eye goo" tastes like. But I don't expect you to know that. I always thought that they eyeball was thick white matter, such as a sliced egg without the yolk. I was told that there's just goo inside the eyeball. Fancy that.

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WarWagon

Yes, it would look like something other than a black hole. I remember at a health fair in high school, they actually had a machine that took a picture of your eye through the pupil. Was pretty neat, if I remember it looked a yellowish color with lots of pinkish red squiggles going all over the place. The first thing that came to my mind when I saw it was "embryo".

shakran

Well, assuming the room was dark, the light would shoot out of the pupil like a flashlight. All the pupil is is a hole, like your wife said. It's black because light doesn't reflect back from inside the eyeball to your eye. If you want proof of this, check out your next family photo. See the guy with red eye? That's the flash reflecting off the back of his eyeball and back out through the pupil. That's why redeye reduction flashes blink several times before the picture is taken -this shrinks the pupil and reduces the size of the hole, so not as much reflected light can get out.

Prince

I had always wondered how redeye reduction worked in cameras. Awesome. This forum is brilliant!

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Lebell

Yup,

Redeye is just the reflection off the receptors in the back of your eye, that is, light coming back out.

I've actually got some great pics of "greeneye" from the ex's dogs (note, I didn't say my dogs).

I should ask the vet about that.

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kazoo

Red-eye can also be eliminated by separating the axes of the flash and camera lens by 6-8 inches.

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mr sticky

Well, it's actually a clear lens. It's surrounded by the iris, holding a circular muscle band to control the size of the pupil- to allow the proper amount of light in, as well as focus the lens!

Eye goo is aqueous and vitreous humors (sp?) that are liquid and gel, respectively!

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gonadman

...and the back of the eye, where the light reflects, is called the retina. This can be seen quite easily with an opthalmoscope, which uses a magnified beam of light.

And I have no frickin idea what eye goo tastes like(okay, so that question was kinda strange...)

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FleaCircus

My guess is that it tastes like chicken. (Everything else does, right?)

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qtpye4u84

well, do you mean the stuff in side your eye? Like a cow eye when you squeze it?
Well, I know what my eye tastes like the outer part thats covering my eye lol its salty. I cave contacts and If i dont have solution and my contact falls out I put it in my mouth and it tastes like salt.
I also got dared to like my best friends eye one time in band camp lol J/k

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Poloboy

Like tears maybe?

Anyway, Do you and your wife have any pets Prince? If you have cats or dogs, I'm sure you've seen their eyes "glow" at some point during the night or in a dark room. Their pupils have dilated because of the dark, so if a source of light is introduced, a lot of it can enter the eye. Many animals' eyes are structured so that light reflects back and forth in the eye, allowing them to see better in the dark. If their pupils are dilated, because they weren't expecting the sudden light introduced, a lot of this light will be reflected back out of the eye and you see it as a coloured glow. This is probably what your proposed scenario (needle with light or something) would look like.

animosity

ask the people from fear factor... maybe write the man show and ask joe. from the look on peoples faces i dont imagine it taste good.

Spanxxx

As an aside to the eyes being gelatinous, I remember hearing/reading about ancient torture methods where they would take a red hot iron poker and gouge out the eyes. If the poker was hot enough, it would actually cause the eyes of the victim to melt before the poker reached them.

This could all be hearsay and folklore, as I have no substantiating proof, or link to at least point you to. I do see how it could happen (the melting part) though considering the consistency of our eyeballs.


ps. keep your damn needles away from my eyes!!!!!!

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Stompy

Anyone ever have their eyes dilated?

I had a lasik screening and they had to do it. They put these drops in your eyes which forces your pupils to dilate to the max so they can get a nice peek at your retina and everything inside. It feels so strange as if your eyes are just WIDE open. Open your eyelids as far as they can go and imagine feeling like that for hours.

You're ultra sensitive to light (obviously) at that point and you need to wear sunglasses if you go outside. It also makes you temporarily far sighted and lasted almost 8 hours for me.

The eye is an odd thing.

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gonadman

I also read about this type of torture. The poker was brought towards the eye, and the cornea would melt and the substance within the eye would bubble and boil. Must have been horribly painful without killing the dude.

I think I experienced that type of pain watching the NFC championship game this year...

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Poloboy

They have two types of drops. One is very short-term, the longer-term typically lasts about 6 hours. I never felt like my eyes were wide open, everything was just slightly blurry, which is normal and is why you're not allowed to drive after having them dilated.

SixEdxMia

So...Once again I've learned something. : ) And I have something to share... I've licked a few eyeballs in my day and they taste like tears and spit...go figure.

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