World-first bionic vision system poised for human trials

Scientists in Australia who have spent more than 10 years developing a first-of-a-kind bionic vision system are now eyeing human trials. The technology works by bypassing damage to the optic nerves, and following successfully trials in animals, the scientists are hopeful it could one day help restore vision in those suffering from untreatable blindness.

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I mean 172 pixels isn’t a lot…

dv said:

I mean 172 pixels isn’t a lot…

Baby steps…

dv said:

I mean 172 pixels isn’t a lot…

You’re a Debbie Downer…

I wonder what kind of patients would be suitable candidates. You’d basically have to be completely blind in both eyes for this to be a good option, but it only works for those who are blind due to “optic nerve damage”.

dv said:

I mean 172 pixels isn’t a lot…

It’s actually not bad.

The number of blue pixels in the human eye is surprisingly small anyway, and we don’t have a problem with that. Let’s see. Blue pixels in the human eye are 0.12 megapixels, or a 345 * 345 pixel array.

OK, so there are a lot more than 174 natural blue pixels.

mollwollfumble said:

dv said:

I mean 172 pixels isn’t a lot…

It’s actually not bad.

The number of blue pixels in the human eye is surprisingly small anyway, and we don’t have a problem with that. Let’s see. Blue pixels in the human eye are 0.12 megapixels, or a 345 * 345 pixel array.

OK, so there are a lot more than 174 natural blue pixels.

This is a spurious comparison, given that the device described here won’t provide colour vision at all. It is 172 pixels of brightness, compared to the approximately 100 million rod cells of the human retina.

dv said:

I wonder what kind of patients would be suitable candidates. You’d basically have to be completely blind in both eyes for this to be a good option, but it only works for those who are blind due to “optic nerve damage”.

Buffy would have some to contribute here …not using the region of the brain dedicated to vision may be a block for some people born completely blind ..for those without any capacity to detect light from dark …I imagine.

There are limits to candidates for the cochlear ear implant for similar reasons as I understand things. The capacity to plug into the wiring in that region of the brain is part of it and for some people the basic wiring isn’t there at all to make the option viable.

Maybe this will be different for this new inovation..here’s hoping.

I went to the paper link.

https://iopscience.iop.org/article/10.1088/1741-2552/ab9e1c

It seems what they have actually done is implanted the thing in some sheep’s brains and stimulated the implant and it didn’t damage the brains. Not really the same thing as saying that it works. It just didn’t do damage.

>>The results indicate that long-term stimulation through wireless arrays can be achieved without induction of widespread tissue damage.<<

monkey skipper said:

dv said:

I wonder what kind of patients would be suitable candidates. You’d basically have to be completely blind in both eyes for this to be a good option, but it only works for those who are blind due to “optic nerve damage”.

Buffy would have some to contribute here …not using the region of the brain dedicated to vision may be a block for some people born completely blind ..for those without any capacity to detect light from dark …I imagine.

There are limits to candidates for the cochlear ear implant for similar reasons as I understand things. The capacity to plug into the wiring in that region of the brain is part of it and for some people the basic wiring isn’t there at all to make the option viable.

Maybe this will be different for this new inovation..here’s hoping.

Most of the bionic eye things are not vision as we know it. The people have to sort of learn how to “read” the effect of a different stimulus to the brain from what you get from a normal optic nerve. I haven’t read much of the research recently, but I think it is a very long way from being useful. Last I checked, they could get phosphenes – the sensation of “seeing” a spot of light. Like if you shut your eyes and rub them and you “see” light. And I think some were being able to tell light or dark. I don’t think they are much more advanced than that.

There is a hella lot we simply don’t know about visual processing. Quite recently it’s been found that quite a bit of processing is done at the retina, before anything is sent to the visual cortex. Given that, stimulation of the cortex looks less promising for what you might call real vision. Other research groups are working on implants at the retinal level.

This is a recent paper overviewing the retinal implant devices in the works.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7198351/

“An update on retinal prostheses”

Published this month.

Section 11.4 tells you about the Australian one. (This is not the one in the OP, which is a brain implant, not a retinal implant)

Section 15, the conclusion, summarizes the great detail in that paper.

And an overview of the work on visual cortex implant work.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6916716/

“Electrical Stimulation of Visual Cortex: Relevance for the Development of Visual Cortical Prosthetics”

Lots and lots of detail about the visual cortex etc.

>>SUMMARY POINTS

Stimulation of early visual cortical areas produces simple percepts known as phosphenes. Threshold currents for detection of phosphenes become lower with training. Stimulation with penetrating microelectrodes and small currents likely activates a region of cortex several hundred microns in diameter. Stimulation with cortical surface electrodes and moderate currents likely results in several millimeters of cortical activation. Electrical stimulation can alter the flow of information through the cerebral cortex. Stimulation of later visual areas, with no concurrent visual stimulation, typically does not result in a visual percept. Stimulation of later visual areas can alter performance in a visual task or distort perception of visual objects. The perceptual and behavioral results of electrical stimulation can be best understood by evaluating the intersection between the spatial pattern of cortical activation and the underlying functional maps.<<

dv said:

mollwollfumble said:

dv said:

I mean 172 pixels isn’t a lot…

It’s actually not bad.

The number of blue pixels in the human eye is surprisingly small anyway, and we don’t have a problem with that. Let’s see. Blue pixels in the human eye are 0.12 megapixels, or a 345 * 345 pixel array.

OK, so there are a lot more than 174 natural blue pixels.

This is a spurious comparison, given that the device described here won’t provide colour vision at all. It is 172 pixels of brightness, compared to the approximately 100 million rod cells of the human retina.

Nobody uses rod cells any more.

WTF they had a 4*4 version shown on QUANTUM or CATALYST or Beyond 2000 or Beyond Tomorrow or something, how first ¿

SCIENCE said:

WTF they had a 4*4 version shown on QUANTUM or CATALYST or Beyond 2000 or Beyond Tomorrow or something, how first ¿

The best in the year 2008 was still 16 pixels, as you’ve said.

You can actually get a half-decent image from 174 pixels by waving the head around. Not enough to read with, though. And would be struggling with facial recognition.

“the Zrenner group has tested their subretinal prosthesis (microphotodiode array with 1550 electrodes) in pigs”. That’s more than enough for facial recognition and reading large print.