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Artificial Retinas Bring Vision Back To The Blind
Patters writes "Researchers from the University of California and the Doheny Eye Institute have successfully implanted a tiny electronic eye implant with a video camera mounted on a pair of sunglasses into 6 patients, allowing them to detect light and motion. The implant is a 4-by-4 grid of electrodes which connects to damaged photoreceptors (rods and cones) on the patient's retina. It works by stimulating the photoreceptors, transmitting signals through the optic nerve to the brain. The implant only works on patients with degenerated rods and cones, and is named after Argus, the Greek god which had 100 eyes. If the implants continue to be a success, the artificial retinas could be available to the public within the next 3 years."
the question is whether your brain is up to of synthesizing a image from a pan and deconvolving the large pixels down to high resolution. There's some evidence it might be able to synthesize the image from the pan since it already does that for your blind spot. And the ganglia in the eyeball do some deconvolution already so that might be possible too.
I guess we'll find out when the blind people tell us.
Some drink at the fountain of knowledge. Others just gargle.
It would be better to grow brand new biological eyes (compatible with the intended recipients DNA), and have those implanted rather than electo-mechanical solutions. One key advantage among many being that such replacements could actually grow with the person, and recipients would not be limited to adults.
File under 'M' for 'Manic ranting'
...it's probably worth pointing out the research already done in various other areas - I believe a few months ago the Univeristy of Wisconsin completed a test whereby a grid of electrodes was placed on the tongue of a blind person, who wore a head mounted camera - light intensity would trigger impulses sent to the grid. Apparantly one of the subjsects even managed to navigate around a maze using it. I'm sure a /. story was posted about it...
But even this was based on previous research - I remember about similar experiments done in the late 1980s, albeit on a far lower resolution and using a extremely pad of electrodes mounted on the chest.
I don't think this is totally the case.
Having some experience with cochlear implants, I can tell you children who are born completely deaf - ie, have never heard sound in their life - often adapt (over time) to cochlear implants.
However, most adults cannot do this - the brain of an infant obviously is under constant development, and so can learn how to "hear" far more easily than a totally deaf adult.
Not really. Human vision develops at the early stage, at the same time as we learn to crawl along as infants. There was once a case where some parents tried "accelerate" their kids development, by skipping the crawling stage, and just using a baby bouncer instead. Apparently, the kid never learnt the concepts of "perspective" and "distance". as a consequence, she couldn't understand why objects changed in size.
There was also a guy in a 3rd world country who had cataracts since he was born. Doctors managed to help him see again, but he could only see colours, but not shapes. He still had to touch the object to get the idea of its shape.
There are so many aspects of vision that we have to learn in order to avoid becoming confused: shadows, reflections, texture, shape from shadow, perspective, not forgetting spacial relationships (partially obscured, behind, inside).
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I think you misunerstand my post. Look at folks who have never had sight. Studies have shown that other parts of the brain begin to use the "dead space" that would have been dedicated to vison. I don't think it is unreasonale to expect that you COULD get super sight.... but something else would suffer as a result.
The brain is a very amazing creation. However, it isn;t sitting around with 90% unused capacity as is the common old wives tail. Make vision better, something else must suffer.
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How about:
- A jack that accepts video signal from a computer for work or GAMING
- Backward or otherwise mounted cameras at all times giving "rear view" (eyes in the back of your head!) appearing off to the side of the main image
- Your personal HUD! News, stock ticker, email, personal alerts and reminders, responding to voice activated commands
- Night vision or infrared
- Television receiver with subtitles
- Zooming lenses
Okay, none of that will be helpful with 4x4 res, but think of the possibilities for future use!
Then again, think of the pranks you could pull on someone by splicing it.
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One thing that happens during early infant brain development - when the low-level brain facilities for vision are also developing - is the mass culling of synaptic connections. That is, the brain initially grows (during late prenatal development) an abundance of synapses, far more than it needs for normal operation. A large portion of these synapses are removed during early childhood (first two years or so), with learning and experience creating a "survival of the fittest" scheme of determining which synapses to keep and which to lose.
It is almost certain that the excessive culling of synapses in the visual centers of the brain that results from not having any visual stimulus during the first two years of life is irreversible. Possibly the brain could be stimulated to produce new synapses in those areas, but it is likely that the process would cause far more harm than good.
What would be the 'resolution' of the human eye? I think its gotta be in the range of maybe 5000*5000 to 10,000*10,000. But maybe its higher. I know I read a cool story by Greg Egan about transferring your mind into a computer and how the visual data was generated by raytracing backwards from the simulated retina, one ray per cell just like how its one ray per pixel. But I wondered at the time how many rays that was.
I've seen a video clip of a person using the implant. He was an older man who had originally been sighted, but had lost his vision several decades ago. An object was placed in front of him on a table, and he proceeded to move his head around in a circular pattern, kind of like a bird doing some sort of mating display. I think this motion multiplied the effective resolution of the device, giving him a better sense of where the object's boundaries were than if he'd held his head still.
After about 20 seconds, he announced, it's a cup, and he was on the verge of tears, and honestly, so was I. Increasing the resolution of the device is just a matter of engineering. The concept works.
> Actually, the blind spots are an artifact of the physical construction of
> the human eye. It's where your nerves leave the eyeball.
*Those* blind spots are only actually blind spots as long as you keep your gaze focused in one spot without looking around -- which you generally don't do, except when you're very sleepy, drugged, or deliberatly focusing your vision on a particular thing that's stationary (and normally when you focus your vision on one thing, it's a thing in motion, so this doesn't come into play then). Otherwise, those "blind" spots have almost no impact on your vision. As your gaze passes over something, it theoretically blinks out for an instant (if it's the right combination of small enough and far enough away), in that your retina is not perceiving it for that instant, but as your cerebral cortex processes and intereprets the informatin it is receiving, it smoothes that over automatically and fills in the blanks for you. The retinal blind spot makes a fascinating "optical illusion" science demo at places like COSI, but as long as you don't stare straight ahead like a zombie, it presents no very significant problem to your vision in practice.
However, the other poster was talking about the rather larger blind spots that result from the limits on your peripheral vision (both horizontally and vertically): in a nutshell, you don't normally see behind your head. Since your head (and whole body) don't generally move *nearly* as often as your eyes, this larger blind area has a much more significant impact on your visual perception.
Cut that out, or I will ship you to Norilsk in a box.