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Severed Optical Nerves Can Be Made To Grow Again
Anonymous Coward writes: "It is being hailed as one of the most significant advances in nerve regeneration in a decade. After severing an optic nerve in rats, neurologists have found a way to reconnect it to the brain so that it once again transmits normal electrical signals. As reported in the New Scientist this achievement is a first in mammals, and may hint at ways of reversing some types of blindness in people. Scientists also hope to use a version of the technique to treat people with spinal cord injuries.
It you can regenerate the optic nerve (or rather, prompt it to regenerate), what about other nerves? Spinal cord? Maybe you could make Rush Limbaugh hear again (or at least make him deaf only to the poor, human suffering and forward-thinking ideas like he was before).
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
that we can connect our brains to fiber optics and record our thoughts? or would that be illegal under the DMCA, since we might think of something copyrighted?
The people most interested in this article can't read it.
Is there an MP3 of chrisd narrating it available please?
http://www.thehungersite.com
The complexity of this discovery compared to our current understanding of nerves can be likened to a comparision between a toaster and a computer.
This is very awesome for those of us who are on our way to blind or know people who are.
(/local/home/curiosity)-#who -u|grep thecat|cut -c 44-49|xargs kill -9
I know of at least one person who could benifit from this. Also, who know where this can lead us? Later on they might find a way to make the paralyzed walk. I just have to say that my hat is off to the group of scientists who smoked enough weed to think this possible, then do it. Honestly, how the hell do they get those wacked-out ideas?
Imagine having a mathematics co-processor, that solved every mathematical equation almost instantly, directly embedded into your brain. Even if only a few people chose to adopt these, the advances they could make for physics and math are staggering.
I know a lot of people would be uncomfortable with implanting technology into their bodies.. but, to me at least, the idea of a society in which information could be wirelessly transmitted in to your brain is beyond cool.
(disregarding the potential for abuse, that is)
I'd rather have those visor-eyes that Geordi gets in Star Trek 8, to be honest.
WHta are you doing to eat for dinner?
WHat is on your favorite floppy disk(s)?
Please answer questions in a truthful manner. Thank you.
that a Barbara Walters interview with Christopher Reeves will be coming up soon.
... better that than listening to the KPMG theme song. Er, oops.
You could've hired me.
does that mean last night's "Kenny Dies" south park was actually right about something?
"But remember, most lynch mobs aren't this nice." (H.Simpson)
-- Joe
A very good friend of mine has a rare problem with the optic nerves in his eyes, which causes his vision to be so blurred that he is legally blind. All tests indicate that his eyes are shaped perfectly; he should have 20/20 vision. Furthermore, the doctors haven't been able to do much for him, since they dont' fully understand the problem. So they try to give him eye-glasses, and magnifiers, which don't do much good.
Research like this, when it might potentially spark a break-thru that could help someone close to you, is always great to see. I hope they make serious progress with this one.
I'm really afriad of what this will lead to: more Christopher Reeves commercials.
The team is currently studying the rats' behaviour to assess how good their eyesight is.
While the rat team is currently trying to figure out how to anaesthetize a large group of humans, and then gnaw their eyes out.
I once heard Oliver Sacks talk about somebody who had been blind their whole life (due to completely opaque cataracts, I believe). A new surgery technique restored the fellow's sight. But when he woke up from surgery, all he could see was an overwhelming mass of incomprehensible color. He couldn't distinguish faces, object, or even simple shapes.
His eyes, it turned out, were functioning perfectly. But because he has been blind during infancy, the visual parts of his brain had never developed -- he had never learned to see.
He did slowly learn, but it was agonizing for him. His newfound sight was overwhelming and sent his brain into chaos. After a long time, with tremendous effort, he could shave for a minute or two in front of the mirror -- but it was absolutely exhausting, and had to finish with the lights off.
Eventually, an unrelated optical infection threatened to take his sight, and he chose to let it run its course. Returning to blindness was a tremendous relief.
Perhaps slightly off-topic, but fascinating!
--Patrick Bateman, Esq.
Will this mean that we can restore the nerves in the tails of mice? Maybe soon we'll be able to cure the obsession of farmers wives with knives.
Or at least, "Recently, Rush Limbaugh lost one of his 5 senses...fortunately, it was only his hearing, so this should have little impact on his daily life."
This can also be applied to robotic prosthesis, and other nerve machine connections. This might allow the synapsis to grow into a mesh/matrix of nerve-electronic component connections.
Im not here now... Im out KILLING pepperoni
The regenerated nerves also carried normal electrical signals, suggesting that they had rewired themselves into the brain, although the connections were a bit scrambled.
None are so blind as those who can not see;
from the article:
The regenerated nerves also carried normal electrical signals, suggesting that they had rewired themselves into the brain, although the connections were a bit scrambled.
Does that mean we don't need DeCSS, once the MPAA requires, via a click thru agreement, no doubt, that we all be blinded before watching any of its movies?
Seriously, this is great news, now we just need to be able to regenerate brain cells, that way corporate execs will have more than one.
Oh, and find the "clue" gene...
;)
moose
.
Have you read the moderator guidelines? Well, have you, PUNK? (and I want a Karma: Gnarly option)
I thought the idea that it was immune system stimulating growth pretty interesting. The immune system releases a lot of signaling molecules at all stages. I'm not an immunologist per se, but I've never heard of any of them stimulating growth, but that certainly doesn't rule out the idea.
The article said that it was just inflammation that induced growth. I somehow doubt that, since everyone who's ever had irritated eyes has felt the fun of histamines and the primary immune response in action. If that sort of thing could make the blind see again, I'd be really surprised, even if it is on a larger scale.
If it is the immune system, I'd bet on cytokines released by helper T cells (those things that HIV targets) simply because these cells release a ton of stimulants. This may be triggered by the nonspecific inflammation like the author suggested, but I'd bet on the helper T as actually secreting growth signal.
If it is possible to use the immune system to regrow neurons, it's very likely applicable in other parts of the body too.
"I may not have morals, but I have standards."
If anyone has any interest in how the brain works and the insights one can gain by looking at what happens when the brain malfunctions, I can't recommend the Oliver Sacks books highly enough. He's a neurologist who studies the brain and has a positive gift for writing about his subjects. Not to be touchy-feely, but he writes about them in a very sensitive way to where you don't feel like people are getting "exploited" for his own gain.
Other tales in his books to whet your appetite:
1) "The man who mistook his wife for a hat", which is the title of one of his books about a man who, otherwise normal, had problems with misconnecting objects to their identities,
2) A woman who could perceive things only on one side (say the left), but not on the other, even though her vision was perfect. When she ate, she would have to eat one side, then turn the plate, eat another half, etc. She was perfectly sane, but just had this wierd perceptual problem.
3) The man who could not make new memories, and lived the same moments over and over. He could remember everything up to an accident he had, but nothing further. Every day he would re-meet the same people. They have to keep mirrors away from him because it freaks him out because he looks too old for himself.
4) The "anthropologist" on mars, who is a pretty famous autistic teacher I think at Colorado. She has perfect image recall, but is entirely without emotions. She actually has her own book that she wrote about what it's like to be her, but I can't remember the name of it (anyone?).
The books are absolutely chock-full of stories like this. If this stuff fascinates you like it does me, I give these books my absolute highest recommendation.
Sometimes it's best to just let stupid people be stupid.
Ok, they can get severed optic nerves back together, and working, that have been cut with a laser scalpel or some such thing. What if they are fixing naturally degraded optic nerves where there is not enough length (damn cat5 cable is just too short...) left? Is there a way of extending the nerves? Are we talking about splicing in "new" nerves that were "grown" in a lab or something else?
Still a very cool development!
Consider the possibilities: With this we can now reconnect optic nerves. The important thing is that if you remember, way back some time ago (can't find link, oh well) a method of drawing images directly onto the retina (assuming the optic nerve was connected still...) was developed. This effectively means a cure for any eye problem.... not too shabby.
Isn't it an already known fact that MOSLEMS' nerve get hooked with the infinite-loop growth?
First they accuse us of being evil.
Then, they did what they did to WTC - several years ago.
Then, they bomb our embassies.
Then, they accused us of being evil, again, after we take out some of their terrorist brethen.
And when everyone think the MOSLEMS' nerve stop growing, for a change, they bomb WTC, and this time they brought WTC down - with over 4000 innocent lives with it.
And when we take action against their terrorist brethen, again, them MOSLEM have the NERVE to call us EVIL - from Egypt to Malaysia to Pakistan - them MOSLEM vowed to KILL US ALL.
What nerve they have !!
Muchas Gracias, Señor Edward Snowden !
a breakthrough would be if I could hook up my brain directly to the video output on my computer.
Actually I weigh 399lbs.
Why do you ask?
-CowboyNeal.
Give it a try. For all of us.
Wow, I am partially sighted and this innovation won't be able to help me or the millions of others affected.
;)
It appears to be a lot of money and intelligent thinking thrown at the problem, instead of solving the cause (again).
Maybe we can give the electric squid RC car we saw earlier on slashdot human eyes, I could certainly use a replacement, and i AM very clumsy
It's really horrible, worse than goatse even!
umm what exactly do you think "nerves" are made up of?
sic transit gloria mundi
...everytime I hear something from New Scientist I can't help thinking about this article. Its often interesting to read, but the results are not from an accountable source - always from some scientists somewhere that have questionable results...
All of the big breakthroughs that are real seem to be reported by actual news institutions.
Its just another straw on the coffin (another nail in the camel's back).
Mod me down and I will become more powerful than you can possibly imagine!
This was reported on syncwater (http://www.syncwater.org) yesterday. Slashdot needs to get up to speed.
don't the scientists need a 'permission' to link to the brain?
That's not neccesarily true... the processing power of the brian lies in its parallelism. Comparing switching speed of neurons to typical network bandwidth and thouroughput of a string of neurons to that of a typical network pipe embarrasses the biological contender.
:)
HOWEVER, on the note of parallelism, it a networking system could somehow be developed that was parallel in nature, this may lead somewhere.
"This is Zombo Com, and welcome to you who have come to Zombo Com" - www.zombo.com
Well, we could repair your optic nerve miss, but it will involve crushing the lens of your eye. You'll be able to see again, but everything will look like it does in a circus mirror.
ôó
I debated until I was blue in the face in high school biology classes that nerve tissue can regenerate if given the right materials and circumstances. Unfortunately, they were too closed minded to realize that regrowing nerve tissue isn't really that hard.
Job? I don't have time to get a job! Who will sit around and bitch about being broke and unemployed then?
FINALY! I have been waiting for _YEARS_ for a breakthrough like this. Man shitty day so far, this makes is worthwhile and them some!!! YEEEES!!!!!!!
I'm legaly blind in one eye, I have almost no depth preception. You know all of those 3d monitors that people keep on getting excited over? Well if Science keeps up its march I may be able to use them one day!! YAAAHHOOOOO!!!!
Need help treating your acne? Come here!
"Although we refer to the optic nerve as a "nerve", it is, in fact, more like to brain tissue."
--Patrick Bateman, Esq.
This will be great when they can apply this to different nerves. John Bobbitt my get himself back to normal after all.
I just hope that this process eventually includes cloning, that'll show the anti cloning idiots... Never argue with stupid people, they'll take you down to there level and beat you with experience.
Geordi La Forge didn't get his sight back until the 24th century!
The man who could not make new memories, and lived the same moments over and over.
Reminds me of Memento. Pretty cool flick, worth checking out.
python -c "x='python -c %sx=%s; print x%%(chr(34),repr(x),chr(34))%s'; print x%(chr(34),repr(x),chr(34))"
The story does not say anything about sight having been regained through use of the technique, only about the degree of regrowth. If any tests on sight were done, they are not mentioned. That makes this result highly questionable in terms of possible clinical value.
There are many things that could thwart the restoration of sight -- for instance, if severed axons joined to the wrong partners, then sight could be kaleidoscoped; or if the axons grew back incorrectly, they might not transmit action potentials reliably.
Given that the lens is damaged in this procedure, it might not have been possible for them to test sight, but assuming there are other possible sources of crystallins, a followup experiment that tests for sight restoration should be this team's first priority. I'll go out on a limb and predict that 30% regrowth plus probable kaleidoscoping will prove to be only barely useful.
Tim
One thing I have to wonder about is if the nerves grow up the 'wrong' pathway, and how long it will take the brain to sort it out.
When I was 15 years old, I put my hand through an old glass door while trying to open it. The glass sliced through my right wrist, severing pretty much everything (apart from about half of one tendon). I probably don't have to mention the large quantities of blood that went everywhere.
Six hours of microsurgery, and it was put back together again...followed by three months of three hours a day physiotherapy.
The thing I found fascinating was that when the median nerve [0] (the nerve that runs up the middle of your wrist and supplies your index finger to thumb and half your palm) is that some of the nerves went the wrong way. I could stroke part of one finger, and the sensation would come out somewhere else - like a different finger, or a different side of the finger. It was...well...very weird.
However, it didn't take long for the brain to fix it. After a short while, the brain learned the error, and sensations came out in the expected place.
It's one thing when this happens to fingers - but I wonder if you'd need some kind of "optotherapy" to coach the brain to fix the image problems you'd get with optical connections wired differently to how they were before.
[0] Movement of the fingers is controlled by the muscles in the forearm. The median nerve does sensation.
Oolite: Elite-like game. For Mac, Linux and Windows
Oh I see ...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
My girlfriend introduced me to this guy, who everyone refers to as 'Jedi' at the local pool hall. He was your typical programmer-looking fellow with thick glasses. After we met, she told me about how he used to be fully blind from an accident and went to europe to get experimental surgery and is now able to see perfectly fine with the aid of glasses.
I know of quite a few stories about people in areas outside of the united states received advanced medical treatment; this is the first I actually know personally.
The really amazing thing about Jedi is that he could actually shoot a very good game of pool while blind. He would have his friend use a cue tapper and tap on the X/Y axis of the table to tell him where the object balls were at. I met him after he got his sight, but none-the-less an impressive feat.
I would recommend to anyone interested in alternate surgies than what america has to offer to check into the european medical field and you may be surprised. I wish I had more information about him, if anyone is interested in any further information post in my journal and I'll get a hold of him.
Dacels Jewelers can't be trusted.
A theory explaining why some nerves don't grow back is touched on in the article: it can cause more damage than good. They even noted that connections may have been a bit scrambled.
Think about waking up after such a surgery and seeing only (the biological equivalent of) TV snow. Splendid. You may be able to tell when there is light in front of you (as you can tell when a TV that only displays snow is on), but I don't think the human brain is capable of forming a pattern out of gibberish.
The same thing would happen in the case of a spinal cord injury - the density of nerves there is far too dense to guarantee they reconnect themselves properly. Think of waking up after spinal-cord reconstruction surgery to feel a large, shooting pain in your left leg. But in actuality, someone is tickling your right toe.
For you computer people, think of severing a large bundle of wires or fiber optics with a backhoe. Instead of splicing each wire or fiber back together by hand, you decide it would work just as well if you just pushed it back together and hope each one connected to the one it was connected to before. Heh. Not likely.
They did this with horseshoe crabs a looooooong time ago. Now, setting aside that a horseshoe crab is more like a dinosaur than it is like a human, they were able to use a *sonogram* (yes, sound waves) to measure the electrical impulses of the thing's eyes (got me how they did it...) then sever and reconnect them with specially soothing frequencies or something like that.
Human eyes are totally different, but the procedure has been done before...on a much less complex organism.
I used to live with a dude who was going for his PhD in Biology. His research was something related to this healing of optic nerves. He would take all these frogs and chop their optic nerves in different locations and then get them to somehow heal. The problem was, if he chopped the nerves in certain places, the nerves would heal incorrectly... the left eye's nerve would connect to the right's and vice versa. So then they would do these experiments to see if the frog could adjust to his new wiring. The funniest one would be to take one of these frogs, and put some food (a fly) in front of it, slightly off-center to the left for example. Since the frogs vision was reversed, the frog would hop to its right to try to get the food. I don't think any of them ever learned how to catch the fly after they were rewired.
Fischer D, Heiduschka P, Thanos S.
Lens-Injury-Stimulated Axonal Regeneration throughout the Optic Pathway of Adult Rats.
Exp Neurol. 2001 Dec;172(2):257-72. [PDF]
Apologies to those who are unable to view the pdf. (If you're not on a campus who subscribes to idea library, I don't think you can access it.)
Unfortuantly, these researchers still haven't purified the unknown factors that appear to be responsible for nerve growth. (They're in experimental opthamology... so it's not unexpected). Until these factors are purified and their functions described, nerve regrowth therapy will be difficult, if not impossible. Additionally, as some posters have pointed out, there are significant differences between rats and humans, and it remains to be seen if the same factors released by lens trauma are able to produce the same effects in humans or other model organisms. (But the posibility of non-applicability doesn't mean that rats and mice shouldn't be used, it just means that you need to test results obtained in them before applying them willy-nilly to other systems.)
http://www.donarmstrong.com
Finally they punctured the lenses in the rats' eyes
The old threat now seems like a remedy!
Curious, do the lenses heal after the puncture damage? Seems like a sad trade to get your nerve back but lose the ability to focus.
--- -- - -
Give me LIBERTY, or give me a check.
I have a point in the middle of my vision in both eyes where I can't see... similar to macular degeneration... perhaps this will lead to the growth of cones and rods transplants... I want my vision back!!!
||| I still can't believe Parkay's not butter.
If this could fix spinal cord injuries, this means that Superman (Christopher Reeve) might actually WALK AGAIN!!!
WOO HOO!
Hey.. While we're at it can we get Stevie Wonder a peak? Just a peak? I mean if anyone deserves their site HE does. That man has got all the money in the world and can't tell if is in 1's or 100's... HE needs this process...
I hate to rain on several respective parades but optical nerves, albeit from rat embryos, could be made to do grow back about 11 years ago: I knew this because I worked with a research group at Guy's and Tommmy's in London who did this while deciding what I wanted to do at university.
The increased length is a bonus but not particularly important: They proved that the nerves formed synapses with the other nerves in the brain by shining light on the eye tissue and oberving the rats' pupils shrink in response.
Otherwise, the article is excellent.
Elgon
It'd be nice to see stereo again...
Best Slashdot Co
Close...
The oflactory nerve (aka Cranial Nerve I) is not a 'nerve' but rather a direct extention of the brain.
I am fairly certian that the optic nerve (cranial nerve III) is, outside of the dura and therefore is a nerve.
DJMD - The fourth man - Planetary
I suffered some nerve damage back in junior high many years ago. No, it wasn't from worthless teachers or bad food (although...). I had a wrestling accident in eigth grade. My right solder hit the mat in such a way to pull/pry the arm from the socket. Didn't feel to great. The good news is that I still wont the match, on points. The bad news is that tore the rhomboid muscle and stretched a brachial plexus nerve. The muscle is the muscle that sits at the base of your neck, more so on the back. With your right arm at complete rest, push in on the soft muscle a couple inches out from the spine on the back a couple inches below the top of the shoulder with your left hand. Not on the scapula, closer to the spine. Nice and soft, right? Ok, raise your arm just the slighest from the shoulder. Hard as a rock now isn't it? That's the rhomboid. Most of the arm function is lost when you injure that. The nerve I stretched runs around the backside of the shoulder to your hand. It controls things like touch, grip, etc.. of the hand (there are many nerves in that vacinity). I lost all feeling in my right hand by the next day. It came back a month or so later, fortunately. The doctor strongly warned against wrestling again because of the chances of me severing the nerve in a future accident. I wonder if treatment like this could have worked on my shoulder...
first make the rats blind? i'm sure that they could have used 3 blind mice to test it :)
... that I don't have to be one of King Oberon's bastard sons in order to regenerate now?
******
"I do not play at being God -- I AM GOD!
There was a recent incident here in Australia where an accident victims fingers were transplanted from one hand onto the other...
One hand was severed during the accident, the other hand was crushed, they took the good fingers from the severed hand and put them on place of the crushed fingers. Wow.
*** I am the real stylewagon
apparently, after wearing glasses that invert your vision (everything looks upside down), after about 12 hours your brain will correct the problem and everything will look the right way up again ... the brain is a pretty amazing thing. how long till machines can self-heal by completely changing their functionality like this?
Smoking weed can enhance creativity thus leading to discovery. Though I agree it wasn't the weed that got them there. Marijuana is just a tool.. Only those who have used it can judge its usefulness.
smoke a joint
Close again... The retina is probably most accurately described as part of the brain. A strong argument for this description comes from looking at how the eye develops embryologicaly. Also, there are four layers of neurons in the retina, just as there are four layers of neurons in areas of brain cortex which are phylogenicaly old. (hence the term neocortex for cerebral cortex, which has six layers of neurons and is a recent evolutionary design.) The cell bodies of the neurons making up the optic nerve are in layer four of the retina and synapse with neurons in the thalamus, another phylogenicaly old brain structure. So, it is "brain all the way down."
So, should we call cranial nerve II (you wrote III, but you meant to say II) a "nerve?" or should we call it a "tract?"
Glad you asked. The real distinction is between central nervous system and periphrial nervous system. PNS neurons tend to heal, while CNS nerves do not. It is believed that this has much to do with the differences among the cells which provide support for the CNS vs PNS. For example, the myelin in PNS is provided by schwan cells, while the myelin in the CNS is provided by oligodendricytes, and there are many other differences in the "support staff" between CNS and PNS.
So, you ask, is CN II really a nerve or is it a tract? Well, if you look at it closely, it is realy part of the brain, and therfore properly called a tract, but the convention is to call it a nerve until it reaches the optic chiasma, then call it a nerve. But whatever you call it, it is very differant than the sort of nerve which gets cut when one, say, puts their hand through an old glass door.
It could make a difference. Once they can reconnect an optic nerve, eye transplants start becoming possible.
Once they can reconnect an optic nerve, Head transplants start becoming possible!!!
Starting to get the picture?
so we're the theives? how about charging $18 for a CD that cost under $0.10 to make? What? Production costs you say? What? Still leaves the other $15 unaccounted for. What? Musicians you say? Ok, you probably give them about $5. What? You keep $10 for yourselves. Hmmm, who's the thief here... it's not that people WANT to take money from the musicians at all, no, we're fully prepared to give them what they deserve for their talents. It's that we refuse to give *YOU* bastards ANYTHING for the years of exploitation you propogated. It's your own fault, don't blame the reaction for your action. Don't hate the player, hate the game. Oh, and please begin to worry about your copy-proof CDs. Those will meet a similar fate that the "unhackable" DVD did when DVD met decrypting algorithms. For every action, there is an equal and opposite reaction. Come out with "unhackable," and it's hacked within days. Get a clue, man.
- --=I un-status the quo=-- -
There have already been studies done with people that wore lenses that inverted their vision. They were forced to wear these lenses for weeks at a time. After about a week, their vision righted itself -- they saw perfectly normal. Of course, when they removed the spectacles, they had to readjust again.
Provided all the information is intact, I don't doubt that the brain could unscramble it. I would imagine when we were newborns we couldn't see too well either -- we just don't remember it.
-------------------------------------------------
I'm a graduate biochemistry student, and I work in a lab that does biochemical characterization of the crystallins of the lens of the eye. I am extremely skeptical of the theory that the crystallins are in some way mediating this response in the nerve cells.
It is a long story, but the crystallins in the eye serve an essentially structural role. They're present in an absurdly high concentration in order to up the refractive index of the lens tissue. The proteins that evolution recruited to the lens were selected because they resist unfolding and aggregation at high concentration (and, one set of crystallins are thought to help with preventing aggregation of the other crystallins...).
In any case, that tissue is just barely metabolically active (mature lens cells are non-nucleated), and the proteins present have, at most, only vestigal enzymatic activity. From everything we know about crystallins, there is no reason to think that they could ilicit this kind of response. They are highly stable, rather inactive proteins that evolved to last a long time and not mess with stuff.
I don't dispute the study. I just think that the immune system response is a much more plausible explanation.
!splut
The angel in the oatmeal.
I saw this article and was happy :)
;)
Losing my eye when I was seventeen was disheartening...but everyone always told me that someday science would be able to overcome the optic nerve damage the car accident caused...
NOW IT'S CLOSER! Where do I sign up to be a human test candidate? It's funny seeing with one eye but still dreaming with two eyes...maybe I can reclaim that basketball scholarship
...Spooker
after looking at the computer monitor for hours when i get up everything tends to be red - likewise if i lie down in the sun for a few minutes with my eyes closed enough red light gets through my eyelids so when i open my eyes things tend to be green...
watching 25/50(/whatever)Hz pal TV in a dark room before going to sleep is a bad idea - when you turn it off you get annoying flickering - i guess my brain can counter act the perception of flickering TV by adding its own pal signal!
to se Superman fly again.
Facinating, I'd like to read mroe about that, and how it relates to the way vision systems function and evolved. Have any sources?