I was sitting at my first color and light lecture the other day, after first 25 minutes of which I heard more about color than I ever thought possible. So, about 1.5 hours into it, my mind began to wander. My prof kept repeating, "eye-brain," "eye-brain," and a student finally asked why. So my prof dropped this phrase, saying that some scientists suggest that the eye is a part of the brain that is exposed. At this point my eyes and mouth widened. So, please tell, did I hear him right, and please direct me to the doctoral research work that would support that statement. Many thanks. PS. To any professors/teachers at these forums: never, ever drop anything in the middle of a lecture, bc google is not helpful.
It is just a suggestion, I have never heard of this before and I don't agree. The eye isn't a part of your brain exposed, it is simply a tool of the body which captures light information to be interpreted by the brain. I find it to be hazardous endeavor for nature to have the brain exposed to outside dangers.
Sarge: And those incredibly sensitive organs you men call weenies dangling out there is not? I can't say I've heard of this but the eye itself is, apart from the brain, almost a replica in its complexities. You've got millions of neural networks in there all talking to each other beneath tangles and tanlges of blood vessels, its incredibly sensitive (even though the brain lacks pain receptors) and the the way it functions mirrors those of the brain's- in reverse. Give it a picture, it reverses it and works backwards with the brain. The brain in much the same way works the same fucked up way- left for right and right for left. But if I say the eyeball itself is just the brain exposed and trying to look out, then I might as well say anything attached to the brain and just as complex is a brain extension- the spinal cord then is my brain peeking down my back. Does that not sound silly?
Sensitive yes, absolutely neccessary for survival? No...unless we are talking about the whole species. I am not saying that our neccessary features are not at harm (The brain isn't that well protected against dangers is it...quite easy to split open the noggin) but I am coming to the conclusion that the part of the brain would not be exposed this way...same way the heart isn't. True and if one eye is useless the others continue working with half the perspective same with brain if the corpus collusm is damaged.
Look at the development of the eye: The eye develops at the site where the optic vesicle makes contact with the head ectoderm. What is the optic vesicle? it is a bulbous outgrowth of the diencephalon. What is the diencephalon. That is part of your embryonic brain. Where the optic vesicle (brain) makes contact with the ectoderm the lens placode is formed. The lens placode invaginates and forms the lens, the optic vesicle (brain) forms the optic cup which will differentiate in 2 layers. The outer layer develops into a melanin pigment layer and become the pigmented retina. And the cells of the inner layer proliferate rapidly and form the neural retina. Part of them are retinal ganglion cells wich send their axons to the brain though the optical nerve. Pretty standard stuff.
This string reminded me of an odd piece of information. People who received corneas from people who died of Creutzfeld-Jakobs disease contracted the disease themselves. That suggested that nerve tissue was responsible for the transmission of the disease, one of the many pieces of information that helped discover how mad-cow disease is transmitted.
Actually, the brain is only a word as anything else. Everything work together. The same principle that the brain was formed after, your body was formed after. I heard that most of the genes are active in the brain though. Maybe if we tried REAL hard, we might be able to think with our ... small head Please Register or Log in to view the hidden image!
I didn’t find much. I, not being a neurobiologist have nothing against the idea that the boundary between brain and eyes is somewhat soft, hence the idea that the brain and eye share the retina seems ok to me. ‘The retina, a sheet of neurons at the back of the eye that any physician can see through an ophthalmoscope, is the only part of the brain that is visible from outside the skull.’ http://www.hhmi.org/senses/a130.html Or this might be a good place to start, The Retina, An Approachable Part of the Brain, John E. Dowling, Belknap Press of Harvard University Press, 1987 So then the problem, if the retina can be considered part of the brain, why not the whole eye? Please Register or Log in to view the hidden image!
yeah it really depends on what you consider the brain to me. THe sensory organs to me are input devices to the brain gated byt he thalamus. BUt i can see where that statement would come. The Eyeball(cornea/aque___ humor) itself acts as a filter to which is collected at the retina which is also part of the brain and if you consider the retina to be part of the brain then yes the eyeball is too. But as far as I know the optic nerve is the boundray of teh brain and the eyeball is just an input device
That monkey: No. Let me tell you something about academia, Spurious. It has a tendency of bieng flamboyant with its jargon, boring its audiance brain by brain with its technical jibberish. Its speaker will snatch the chance to talk about bulbous outgrowths and placodes where somewhere in there he'll forget what the question was and who he's answering becuase he's too busy with anatomy lessons. And THAT, dear boy, is what is 'pretty standard stuff'.
Konek: Fuck off, commoner. Imagine Einstein detaling the electrodynamics between neutrinos and quarks, bobbing on the edge of his seat as he's off to scribbling the workings of time dilation with fancy Riemman curves.......only to realize hours later that his listener was a layman honestly curious about the nature of light and now he's not only forgotten the question but he's put him to sleep. Einstein would have never been as likeable and as genius without me spelled right: gedankens. Simple, but not simpler. There's charm in that. Not the monkey.
On the contrary, its jargon is aimed to be precise. How else can you have a system based on peer review? Spurious' answer explained how the eye is formed and how it relates to the brain. Considering the original question, whether the eyes are an exposed part of the brain, I suppose Spurious' post is relevant. Moreover, since this is obviously a discussion about the physical relation between two parts of our bodies, how do you propose we avoid anatomy?
Nuerologically, the brain pervades the entire body. Reflexes, residual images, and "muscle memory" are some examples of "brain" functions, or nueroprocessing that occurs outside the skull. Counting with tactile clicks, we partially think "in" a finger.
I think spurious monkeys post got to the point, it is a mix of tissues that are essentially skin and brain. Just what you'd want to do. Make an organ that is part skin and part brain. The nerves in the eye do a lot of signal processing to sharpen edges etc. so you want it to be very "brainish" compared to some more distributed senses that are completely processed in the brain qua brain. By the same token you need a special protective/optical covering to ensure light entry with some protection from the outside world. I'd be curious to know whether at the surface the density of nerves is comparable to skin in sensistive regions ... say your dangling member ... or whether they are mainly deeper. This would help determine whether it is more a juxtaposition of brain near a specialized skin layer or a true integration of the brain into the skin layer.
