Seeing With Your Skin? 138
Iddo Genuth writes to tell us that a researcher from Tel Aviv University is exploring the possibility that humans may be able to "see" via their skin. Professor Leonid Yaroslavsky hopes to utilize this possible technology to find solutions for the blind in addition to new types of image capture that might be able to work where conventional lenses fail. Unfortunately he has a long uphill battle ahead to convince others that his theories are possible. "The lenses currently used for optics-based imaging have many problems. They only work within a limited range of electromagnetic radiation. Relatively, these are still costly devices greatly limited by weight and field of view. The imaging Professor Yaroslavsky has in mind has no lenses and he believes the devices can be adapted to any kind of radiation and wavelength. They could essentially work with a 360-degree field of view and their imaging capability will only be determined by computer power rather than the laws of light diffraction."
My eyebrows are raised (Score:5, Insightful)
As a vision scientist, my eyebrows are raised. I am highly skeptical for a variety of really, very good reasons...
Re:My eyebrows are raised (Score:5, Funny)
Yes, but does that increase or decrease what you're seeing with your forehead?
Follow the money. (Score:2, Interesting)
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WTF? Tel Aviv University is a very decent research institute that has made many important contributions to science. No, I am not and have never been affiliated with them, but the page you are referring to is obviously that of an alumni organization. And yes, they do raise money for the university, that is what alumni organizations do.
As for Yaroslavsky (the prof working on this "seeing skin" project), I know neither him nor this project (at least not more than the press release states), but his publication
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Obviously the skin can detect many wavelengths of light--I am having trouble jumping from this thought to the thought of the skin resolving those sensations into an image.
Blind people seem to be able to do that with braile. Maybe a pattern of bumps can work in a similar way to a pattern of warm spots on the skin.
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I recall Richard Dawkins saying that eyes tend to evolve from photoreceptive skin cells.
The brain is the most important organ that "sees"; it's the thing that does the image processing. Or, if you look at it another way, the brain constructs the image from available data.
If it were medically possible to stimulate a patch of skin cells to transmit more light information to the brain - and correspondingly stimulate a neural pathway (who knows, maybe even all the
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It's nothing like echolocation. First of all, echolocation is active scanning, vision is passive scanning (nobody can detect you're looking at them, however you can tell if someone's using echolocation). Echolocation is dependant upon 1 or 2 sensors, while vision needs thousands (and prefers millions) of sensors.
The calculations are explained in this link :
arXivBlog [arxivblog.com]
The article makes several good points. After minimal practice you are able to identify the location of the sun blindfolded.
A bit more practice a
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After minimal practice you are able to identify the location of the sun blindfolded.
Some people actually have to practice that? Simply turn around until your face gets warm.
Nevertheless clearly we can detect that radiation.
I dont' think we detect the radiation. We detect the warmth the radiation produces in our skin. So it's not really different from feeling warmth by touching a hot object (both rely on our skin getting warmer). For the rest: i think it's quite possible put maybe this is a differen effect. In pitch-dark rooms you sometimes can "feel" close walls or large solid objects.
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In pitch-dark rooms you sometimes can "feel" close walls or large solid objects.
Are you talking about rooms you're familiar with or unfamilar rooms? For example, say I blindfolded you and stuck you in with zero light and did not allow you to speak ('cause that may mean that you can use echoes as a cue) would you be able to tell where the walls were? If the answer is yes, then that needs to be investigated. Note also that, perhaps, your walking may produce subtle echo effects.
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Microgravity
CC.
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From quite a distance ! Just imagine you live on a tree and only realize that it is burning right under you — would'nt it be of some 'evolutionary advantage' if you were able to detect the fire earlier (without actually seeing it)?
CC.
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As I understand it, that's more of a matter of the brain rewiring itself to interpret the signals coming from that patch of skin differently than any limitation of the nerves in the skin itself. [wikipedia.org] There is an interesting account of what this is like in an old Wired article [wired.com] around page 5 the author experiences a rather sudden shift as his brain learns to interpret visual signals differently.
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It need not necessarily be an image — a representation of the environment would (does) suffice (and of course it needs a lot of practice to achieve). On a side note, the formulation using the concept of an 'image' (to me) supports the idea that perception is very heavily biased towards vision (which, if you think that balance and adequate proportion are crucial has implications on its ow
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My mother is a teacher and used to work with children who were totally deaf and blind. I was amazed to see how aware they could be of their surroundings, and how much they could learn, though all of their communication was based on touch.
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But surely as a scientist you have an open mind? I don't think they are talking about 'seeing' the way we see to read. The forms of 'skin vision' cited are all ways to detect electromagnetic radiation but none of them would allow one to, for example, read Slashdot. There is vision and there is vision. I think in this case they are just using the term a bit loosely. I'm a bit skeptical about some of the forward looking claims as well, but this might just bear further research.
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Each scientist has a certain balance between open-mindedness and skepticism. I personally favor open-mindedness, even if it comes at the cost of adopting the occasional wrong idea, but I think skepticism is more common. More open-mindedness can improve the uniqueness and number of your ideas, more skepticism their chance of success and the rigor with which they are pursued.
Or, to put it another way, there is an ROC curve for accepting ideas. People who are more skeptical are gaining specificity (less accept
Re:My eyebrows are raised (Score:5, Interesting)
Argh, too many windows open on the desktop and I clicked submit accidentally before elaborating.
My first concern is that this little "story" or press release has been either re-released or duplicated on various sources verbatim for weeks if not months and I've yet to see anything in the scientific literature about it. Publishing scientific progress in the popular press before peer review typically means bogus science to me.
There certainly are photoreceptive skin cells in "lower" vertebrates and invertebrates that do transduce photosensitive information. However, any experiments I've seen in the literature or in popular press (or even weird Soviet 1960s "dermo optical" experiments that have attempted to evaluate "skin vision" in humans have failed or not accounted for temperature or other confounds.
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i know what peer review is!!! (Score:2)
If you are not aware of the problems with peer-reviewed journals in the last decade or two, you only need google for "peer review" and "scandal", or "peer review" and "problem".
In recent years it has failed to be a reliable system. All I can say is that when blatant scammers can repeatedly (and apparently easily) fool the New England Journal of Medicine, and Nature (to name just two popular peer-reviewed examples, and not to mention more field-specific journals which
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...the system has largely failed.
Well, it's still less broken than "No seriously, this snake oil works!"
I was in a lecture about research ethics, and the professor pointed out that research relies a lot on the honor system by necessity and also because it usually works. As I alluded to earlier, peer-reviewed is without a good alternative. What more can we do than peer-review? Lie detector tests?
Hmm... actually...
Well anyway, there's also the fact that few researchers intentionally fake their results (intentionally is key of course). Y
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You don't get into research for the money or fame. Most researchers get into it because they're genuinely interested and want to find answers, advance human knowledge, and help people. With that as your motivation, what point is there to lie?
Nice. If I happened to intentionally lie, at the end of the day the journal that publishes my paper will not lose face. I will.
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But also, keep in mind that sometimes, peer-review serves to filter OUT perfectly legitimate research.
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But the system is seriously flawed, and we should seriously consider how to do it better.
I can see bigger problems with every possible alternative.
Having no review at all would not only allow crap to get published with good results, the good studies would also get weakened. Often times, reviewers comments set a higher standard, and researchers strengthen their papers in response. We get better papers with peer-review and less bad ones. Generally it doesn't keep out legitimate research, it delays it at times, but what it contributes is more valuable.
Having non-experts review papers would be a
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There will always be the problem of deliberate, premeditated fraud. But there is a lot of room for improvement on the OTHER end: the effects of professional jealousy and "covering your neighbor's back", to mention just a couple of the causes of peer reviewers rejecting "unpopular" research, which happens more commonly than is often acknowledged.
Education about this problem, and reminding those "peers" to be on
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Yes, but getting back to what I think was the point of this, the fact that "you can see with your skin" hasn't been published in any peer-reviewed journal and instead is being published through blurbs like this is a good reason to reject it. The asumption in cases like this should be that it's not published because it's crap, not that it's not published because of a flawed peer-review system.
To an extent... (Score:2)
Once again, you must be careful not to tighten your filter so much that you filter out the good stuff... not all legitimate research is performed by educational institutions or corporate labs. In today's atmosphere, many of Edison's "breakthroughs" would be rejected... just as Scientific American awarded honors to someone else for inventing powered flight because it simply did not believe the accounts of the Wright Brothers, and their err
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In recent years it has failed to be a reliable system. All I can say is that when blatant scammers can repeatedly (and apparently easily) fool the New England Journal of Medicine, and Nature [...]
I read Nature and I still fail to see what you're on about. Give me specific examples that highlight the perceived "problems". If I google what you suggested I get a whole heap of results from popular media -- not exactly what I call reliable. Sure, journals (and peer-reviewed papers) are not immune to abuse; I just don't think this is a new "problem". To say that the system has "largely failed" is a bit extreme, in my opinion.
Jesus, do you take me for an idiot?
Of course not.
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http://physicist.org/tip/INPHFA/vol-8/iss-6/p12.html [physicist.org]
Here is another:
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1994041 [nih.gov]
I did not mean to imply that Nature was a particular problem. Rather, I meant more along the lines of "even Nature has been a victim". Nature has in fact been in the forefront of the whole peer review discussion.
And maybe my statement was a bit strong, but I also object to another problem with peer review that often goes unacknowledged: that
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There's no lens to define where the light is coming from when it's reflected to hit the skin
Sweat can bead on the skin and act as a lens, though for evolution of sight it would probably have to be from an aquatic genesis to have become such an ubiquitous solution on Earth, perhaps a membrane protecting sensitive nerve cells becoming progressively thinner generation after generation, improving both in sensitivity and ability to focus as it becomes naturally selected for improved chances of survival both offensively and defensively.
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I remember reading about this in one of those X-files type books in high school ("Strange Energies - Hidden Powers" and "Mysteries of the Undead").
One of the claims was that people could tell which colour a sheet of paper was, even with their eyes closed. They said that blue or purple would "feel colder" than a colour such as red or orange. Since skin can feel infra-red radiation (heat), maybe this was possible.
But they never tested it with a sheet of paper underneath a plastic cover, so the case remains un
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As a theatre lighting designer, I'm not skeptical at all. In fact I have made use of this very phenomena.
As part of a workshop for a contemporary dance show I set up a bunch of tightly focussed beams and pools of light and then had the performers navigate around the space with their eyes closed. In a suitably darkened space, you can feel when the light hits you. I'd say the sesitivity is more the infrared portion of the spectrum, but it does work.
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Whilst I'd agree that vision in the sense that we know it is unlikely to be replicated through the skin, the sensitivity of the skin and of the body in general allows a great deal of information from the body's environment to be perceived and, effectively 'seen'. For practical evidence you only need to look into areas such as internal martial arts, where such perception is often deliberately trained to some degree or other.
Re:My eyebrows are raised (Score:4, Insightful)
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Actually it should: science doesn't work through faith. The word or untested hypotheses of even the most distinguished scientists isn't good for anything besides deciding what to test next. If Stephen Hawkings said Hawkin's radiation leaks out slightly faster from black holes than he thought and didn't offer proof, there would be plenty of people who would investigate I'm sure, but it wouldn't be accepted as more than conjecture, even though it's named after him.
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Re:My eyebrows are raised (Score:5, Insightful)
Further, I would say that being open to criticism and being able to accept that, move on and improve (based on the criticism) separates the mediocre from the brilliant. It doesn't matter how much knowledge you have. We all make mistakes and we all overlook things. We all say silly things now and again.
This is what makes the "science" of Global Warming so frustrating. Criticism or scepticism is anathema, and we hear the constant chant that "the debate is over". Real science thrives on argument and experiments, and not on ad hominem attacks.
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Well, that's because it's no longer an academic question. SOME of the skepticism is "economically motivated" and therefore impossible to satisfy. There's also the factor of "if it's right, then waiting until it's a fact will be too late." As someone who won't lose money directly from cutting our use of fossil fuels, of course I'm going to say we should cut them now and potentially have done it for nothing than not cut them now and wish we had.
The science of global warming is now only used as a bat in the
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Global temperature can and is being constantly monitored by satellites, which measure the infrared radiation from Earth's surface; these measurement show that the global average temperature is increasing. Numerous indirect observations also support the same: the Arctic
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Faith, to a certain degree is absolutely necessary. One must have faith in the reliability of reason itself, the foundations of mathematics and effectively believe that, if basic physics isn't on sound footing as it stands, then it can in principle be placed on sound footing given sufficient information... or something like that.
That said, the amount of stuff that is done based on faith in one's fellow 'scientists' is scary, and I'm not going to name names here.
Re:My eyebrows are raised (Score:4, Interesting)
a) Where did I say that I have an "education"?
b) Why do you think that being sceptical is bad?
c) If you think that by typing "skeptical" (mirroring the OP) was bad, then you miss the point.
d) What did I say that sounded "elitist"?
e) Where did I imply that all good scientists must think like me? (Apart from adhering to basic principles)
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Or at least google "passive voice."
Hope springs eternal (Score:3, Funny)
Of course, like any memories from the 60s ...
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...it makes you want to smoke something and listen to the beatles?
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Was that YOU with the groovy acid at Woodstock??? Long time no see! Let's go burn one man.
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Long time no see! Let's go burn one man.
I know you feel like celebrating, but that's no excuse to go around burning people.
Done before, using different sensory organ (Score:5, Informative)
Dr. Paul Bach-y-Rita who was at UW Madison has done something with vision being projected via electrical stimulation on the tongue. It is called sensory substitution.
I've seen it first hand. It works.
http://en.wikipedia.org/wiki/Sensory_substitution [wikipedia.org]
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...and a project (also from the UW) involving several guys I know, called Visual Taste [uwinnovators.com] does that as well. There are pictures and videos, if the average slashdot reader can be troubled to follow the link...
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"Vague gray shapes. Big dots. Blurry edges."
"Can you see the door? Could you walk to the door?"
"Yeah, I could, if you want me to trip over things and fall down."
"That's a 5-by-5 display. Hold on," says Weiland, "I'm going to up your pixel count to 32 by 32."
Ok, it lost me there. Anyone who can assert where a door is using 25 pixels, without prior knowledge, is obviously delusional. :-)
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Sir, Put Your Shirt Back On. (Score:5, Funny)
"I'm just having a look around."
Seriously, though:
Did anybody else read this, "Homeland Security grants, DARPA grants, or NASA grants would all be just fine."
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He expects these devices to have special sensors for detecting radiation at sea and in airports to identify terrorist threats, innovative night vision devices or near-weightless mechanisms to steer spaceships in space.
Did anybody else read this, "Homeland Security grants, DARPA grants, or NASA grants would all be just fine."
My spidey sense is tingling.
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And did else anyone read this...
"The lenses currently used for optics-based imaging have many problems. They only work within a limited range of electromagnetic radiation. Relatively, these are still costly devices greatly limited by weight and field of view. The imaging Professor Yaroslavsky has in mind has no lenses and he believes the devices can be adapted to any kind of radiation and wavelength. They could essentially work with a 360-degree field of view and their imaging capability will only be determined by computer power rather than the laws of light diffraction."
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And did anyone read this...and think of this? [memory-alpha.org]
Sigh...Geordi's VISOR doesn't use his skin. They translate the electromagnetic spectrum to signals the brain can interpret directly.
However, there's an earlier device [memory-alpha.org] that did use the skin though. It's not what the guy in the article is proposing, but it is like some other much more promising devices that translate information into tactile information, and the user can train himself/herself to use that information.
Since you're a TNG fan (what self-respecting trekkie isn't), you should also note that Dr. M
Hmm. (Score:2)
Light sensitive cells are common enough in various organisms, including in configurations with rudimentary or nonexistent lens structures, so there is no reason to believe that humans having some light sensitive structures on their skin
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But generally, in all the work I've done (my graduate thesis is focusing on optical imaging with a lensless system) most of those kind of things, where you detect the magnitude of the wave-pattern, which in the far field is the Fourier transform, and then reconstruct the phase, it relies on having a relatively well-defined maximum region. I haven't looked at this yet, but I can't see this using techniques like those of X-Ray crystallography or SAR.
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The skin vision thing strikes me as highly unlikely in the "I would expect to have seen some evidence of it occurring, given the amount of time that people have had their eyes close, covered, or damaged" not the "It is a violation of $SOME_PHYSICAL_LAW as we know it" sense.
Are you aware of how REM [wikipedia.org] was discovered? Sometimes these things hide in plain view.
Ummm it's called a sunburn (Score:5, Interesting)
That's probably how the eyes started, as a sensitive patch of skin. Sight would be a different interpretation of pain, with color being different degrees of pain.
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More likely it would have been felt as something like heat, rather than pain. Intensity (temperature?) maps to brightness, not color. Color probably didn't come until something more eye-like had evolved - you wouldn't get color sensitivity from skin, only intensity/temperature. AFAIK color isn't as useful until after you have certain other things - light sensitivity first, to know if something's there. Then directionality, to know where. Then resolution, to know what is is. Color is an additional refinement
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No it isn't. Sun-burns make your sensitive to HEAT, not light. It just happens that sun-light is a common cause of your skin heating up... Of course your sun-burned skin ISN'T sensitive to indoor lighting. You might just as well have said that sun-burn makes your skin sensitive to WATER, since taking a hot shower is painful...
Being able to feel heat is a long, LONG way from being able to perceive light. And if we did actually evolve that way, why can't we see infrared-sp
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Actually, you've got it backwards. Infrared (generally) penetrates further through water than any other wavelength.
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Fishes, being cold-blooded animals, don't give significant amount of IR radiation. Mammals and birds are AFAIK the only things that could be detected easily with IR receptors, and since both are relative latecomers to the game of life, it seems likely that eyes simply haven't have time to evolve IR vision.
It should be noted, however, that several insects have ultraviolet vision.
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You don't seem to know what infrared is. It's not thermal-vision (ala. Predator). It's just another wavelength of light.
While it's peculiar that warm objects emit IR, that is most certainly not the only way to see an object. You'll still see the blocked and/or reflected IR signature of an object, hot or cold.
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Infrared is generally classified as being comprised of 3 different bands. One of the three is highly absorbed by water. The rest are not...
I must also point out that humans don't see ultraviolet, either, so your this is an irrelevant argument, as your pet theory doesn't stand in either case.
I have no desire to argue the point. Believe what you wish.
This was a "psychic" trick in the 70s. (Score:2)
Back then it was called "demo-optical perception." It was complete crap that only worked if the person was wearing a poorly-designed blindfold. In a properly conducted test, this "power" disappeared entirely.
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Back then it was called "demo-optical perception."
Citation needed. Oh wait [ntu.edu.tw].
Sorry, misspelling. (Score:4, Interesting)
Meant to write "dermo-optical perception." As for citations, see Carl Sagan or Martin Gardner.
Let's see here... (Score:1)
From the article: ...humans have an ability to see through their skin...human skin can "see" colors and shapes...controversial ancient instinct...skin vision could lead to new therapies for helping the blind regain sight and even read...future devices with practical applications...special sensors for detecting radiation at sea and in airports to indentify terrorist threats...360-degree field of view....
Verdict: Science fiction.
Obvious in retrospect (Score:5, Funny)
The next stage after talking out your ass.
But? (Score:1)
Skin can see... sort of (Score:1)
That was the most content-free science article... (Score:2)
...ever.
There's no mechanism proposed, just some vague waffle about some organisms having IR sensitive skin and some nonsense about computer simulation. I wonder if there's even anything sensible behind this article or if it's a bogus article about some bogus science.
I see with my skin, on a ladies.... (Score:1)
Yes I can see with my skin when it touches my wife (use can your imagination, not too much imagination).
That will do, Mr. Mash (Score:1)
Eh, eh! Mrs. Slocomb could read two pages of the Times at once if she opened it up and sat down on it!
Disappointed. (Score:1)
Cognitive Science: This sounds familiar (Score:5, Interesting)
I recall a discussion about this in a cognitive science class I took about 3 years ago. Apparently, somebody developed an aparatus that was hooked to a person's back and used pins to provide a monochrome image of what a camera on the person's head was displaying. The interesting part was that they discovered that the visual part of the brain ended up being used to process the images. Eventually the person could see...sort of.
Of course, this kind of trick won't work at all if the person is blind because of a brain problem rather than an eye problem. People who lose their sight overly early on in life will not necessarily develop their visual cortex enough for this type of technology to work. However, people who lose their eyes as adults or teens due to accidents will be fine.
learning braille lights up visual centers (Score:2)
Am I the only one... (Score:1, Interesting)
Can we mark this "Sudden Outbreak of Common Sense? (Score:3, Interesting)
Bear with me, I am thinking out loud here
Very interesting theory. So, we all know that what we see, hear, whatever, is caused by different wavelengths. So, why is it that we can only see in one wavelength spectrum and hear in another? Hmmm. So, if there is a way to slightly shift those wavelengths that another sensory in the body can understand, I doubt you could "see", but, with proper training, I guess it would be possible to train that sense to make sense (no pun intended) of the data.
Then again, I may be totally forgetting something, and this doesn't make any sense at all and I could just be spouting off BS.
However, if this is possible, then this could be a different way of recording data from the world around us. I understand how the eye works, and I understand how a camera works. But, if we use something different than optics to record wavelengths in the visual spectrum, and use a computer program to interperate that data into something we could see.... Hmmm, its a longshot, but it sounds highly fascinating to me.
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I'll add to the other poster who replied.
1- You need to know how the ear works and how the eye works. Completely different mechanisms for sensing.
2- If you need more proof of the difference between EM waves (like light) and sound, consider their speeds. All EM radiation travels at C (basically). Sound travels at, well, the speed of sound. And that speed changes drastically depending on the transmitting medium.
3- Also: I think it's clear that when people can 'see' light with their skin (as in the example of
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Including people, to some extent. Blind folks often tap their canes or make clicking noises, and by the sound they hear back, they can tell if there is some object nearby. I do that myself (though I can see). It's actually helped me navigate when the lights are out before.
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Blind folks often tap their canes or make clicking noises, and by the sound they hear back, they can tell if there is some object nearby.
BTW, if you are wondering, here's how I perceive the results: normally, people have a sense of space around them; an elevator, room, hallway, parking garage, outside, etc. feel differently. In a dark room, when I echolocate a bed-side table (for example), that area suddenly impinges a bit more on my awareness and I know there's something solid there. In terms of touch, it'
Leonid Yaroslavsky? (Score:1)
Crackpots and Marvel franchises (Score:2)
Seeing with our skin... just because it makes "Star Trek Sense (tm)" doesn't mean it's possible. There are a million attention whores in every field of science. Most of them are full of shit. It's just the nature of science, everything comes with a proof, and those proofs can get to your head, make you think you can do anything... well we're not quite there yet, and this is too much of a leap to be believable. This guy's chasing funding so he can be in the spotlight and pretend to work for the next 10-1
One of the oldest scams in the book. (Score:2)
Early psychic debunkers (among them Houdini) openly and convincingly duplicated these feats through trickery. And, under controlled conditions, NONE of the claimants were EVER able to tell the difference between anything less than the presence of very bright light at close range and utter dark
That will come in handy ... (Score:4, Funny)
Batman! Where are you? (Score:2)
Your arch-nemesis has escaped Arkham Asylum! No, not Joker or Two-Face. It's the Ten-Eyed Man [wikipedia.org]! Someone forgot to lock up his hands [seanbaby.com]!
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I think you're describing a form of proprioception.
I wouldn't call it 'seeing', though, since the object you were holding behind your back could change color or brightness without you knowing about it.
-b