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← Formerly Blind Children Shed Light on a Centuries-Old Puzzle

Formerly Blind Children Shed Light on a Centuries-Old Puzzle - Comments

InYourFaceNewYorker's Avatar Comment 1 by InYourFaceNewYorker

Interesting. I wish, though, that they would have explained how their sight was restored, and if these kids were blind from birth.

Julie

Sun, 17 Apr 2011 15:09:09 UTC | #616458

baon's Avatar Comment 2 by baon

Looks like a bit of supporting evidence for Dennett's Multiple Drafts theory of consciousness.

Sun, 17 Apr 2011 17:08:52 UTC | #616488

PhilipK's Avatar Comment 3 by PhilipK

I get the impression the children were indeed blind from birth, surely the test would be meaningless if not. I also would like to know what the actual surgery did, I wasn't aware vision could get fixed from blindness in some cases.

Sun, 17 Apr 2011 17:13:44 UTC | #616492

Neodarwinian's Avatar Comment 4 by Neodarwinian

I can not wrap my mind around this. My personal intuition is that if I ran hands over a sphere while blind I would recognize it when sighted. Fortunately I do not have to depend on my personal intuition because of the scientific method. This experiment opens interesting glimpses into the mind and needs refinement plus replication to see what is really going on here.

Sun, 17 Apr 2011 17:27:25 UTC | #616496

SheilaC's Avatar Comment 5 by SheilaC

Fascinating. And if the kids learn to put sight and touch together in only a couple of days, obviously I WILL get used to these darn varifocals.

Sun, 17 Apr 2011 20:06:25 UTC | #616532

sonnygll's Avatar Comment 6 by sonnygll

Comment 1 by InYourFaceNewYorker :

Interesting. I wish, though, that they would have explained how their sight was restored, and if these kids were blind from birth.

Julie

They did at least imply the kids were blind from birth.

My guess would be a problem with the cornea and/or lens. They can replace those now. My grandfather just had his lenses replaced because of cataracts. It's really something, a 78 year old lifelong glasses wearer who now has 20/20 vision. I didn't know they could do that until he had his surgery.

Sun, 17 Apr 2011 20:36:25 UTC | #616541

mmurray's Avatar Comment 7 by mmurray

They are children blind from birth

Patients who meet these criteria are extremely rare in western countries because the vast majority of cases of curable congenital blindness are detected in infancy and treated as early as possible. However, many congenitally blind children in developing countries often do not receive treatment despite having curable conditions because of inadequate medical services.

Five subjects were recruited from Project Prakash for this study. Subjects YS (male, 8 years), BG (male, 17 years), SK (male, 12 years) and PS (male, 14 years) presented with dense congenital bilateral cataracts. Subject PK (female, 16 years) presented with bilateral congenital corneal opacities. Subjects received a comprehensive ophthalmological examination before and after treatment. Prior to treatment, subjects were only able to discriminate between light and dark, with subjects BG and PK also being able to determine the direction of a bright light. None of the subjects were able to perform form discrimination. YS, BG, SK and PS underwent cataract removal surgery and an intraocular lens implant. PK was provided with a corneal transplant. Post-treatment, subjects YS, BG, SK, PS and PK achieved resolution acuities for near viewing of 0.24°, 0.36°, 0.24°, 0.54° and 0.24°, respectively.

The whole article is here

http://www.nature.com/neuro/journal/vaop/ncurrent/full/nn.2795.html

Michael

Sun, 17 Apr 2011 22:50:09 UTC | #616569

InYourFaceNewYorker's Avatar Comment 8 by InYourFaceNewYorker

Don't feed the troll.

Mon, 18 Apr 2011 00:33:40 UTC | #616588

Aechoes's Avatar Comment 9 by Aechoes

Complexity of shape must play a role in these experiments. A simple sphere, i would have to assume, should be within the grasp of some of the kids' imaginations. Perhaps depth is a tougher thing to imagine - having never witnessed it outside of a tactile sensation - than it seems. Do the lifelong blind dream/daydream in 2 dimensions, like a cartoon? An action figure in their hands would prove to be quite the conundrum.

Mon, 18 Apr 2011 01:19:05 UTC | #616596

nancynancy's Avatar Comment 10 by nancynancy

How wonderful that the children were able to have their sight restored. And how amazing that their brains were able to intergrate touch and vision so quickly.

Mon, 18 Apr 2011 04:00:56 UTC | #616615

Martin_C's Avatar Comment 11 by Martin_C

It is evident from reading many of the posts above just how much many of us take our visual understanding of the world for granted. If you have never experienced vision before then surely the brain needs to learn to associate the new information coming in with what it already knows about the world through touch. I remember seeing an item somewhere about a man who had gained vision after just such a surgery, he talked about how outlines and borders were at first meaningless to him, eg. he could see the curb when crossing the street but did not recognise, as we would, the visual clues that suggest a 3d object which requires stepping over. However, tripping over the curb is probably a good way to get the brain to link the two senses together! I would imagine that that would happen quite quickly and not necessarily require a "complete rewiring of the brain".

Mon, 18 Apr 2011 04:24:04 UTC | #616618

Martin_C's Avatar Comment 12 by Martin_C

Comment 11 by Aechoes :

Complexity of shape must play a role in these experiments. A simple sphere, i would have to assume, should be within the grasp of some of the kids' imaginations. Perhaps depth is a tougher thing to imagine - having never witnessed it outside of a tactile sensation - than it seems. Do the lifelong blind dream/daydream in 2 dimensions, like a cartoon? An action figure in their hands would prove to be quite the conundrum.

I don't think that complexity of shape has anything to do with this, at least at first. If you've never ever experienced vision then surely a straight line is as hard to imagine or give meaning to as is the Mona Lisa. Put it this way, sharks have their electrosensitivity and we don't - can you dream in electro sensitivity? No. If you were suddenly granted this electro-sense would you automatically know what it means? No, I'd say that you would see someone walk by and then learn to correlate the electric sense that occurred with the visual event.

Mon, 18 Apr 2011 04:32:28 UTC | #616619

Aechoes's Avatar Comment 13 by Aechoes

No teacher like failure, eh? The phrase "painful reminder" came about for a reason.

Mon, 18 Apr 2011 04:34:40 UTC | #616620

sbooder's Avatar Comment 14 by sbooder

It seems a shame that the scientists do not have longer access to the children to discover how other sensory information is perceived by the new ability to see. Examples would be fire and smoke, water, ice and the like.

For instance if they saw fire for the first time but from behind a glass screen, so they could not feel the heat or hear the sounds, would they be able to distinguish which part of the picture gave them warmth or made their eyes sting, just from experience.

Could they recognise water just by looking at it.

Interesting stuff this sort of research.

Mon, 18 Apr 2011 08:57:37 UTC | #616659

mmurray's Avatar Comment 15 by mmurray

Comment 5 by SheilaC :

I WILL get used to these darn varifocals.

The brain is a wonderful thing. After I got my first set I didn't need to wear them all the time as my sight wasn't that bad. One day I was outside without them on and I couldn't see a street sign clearly. Suddenly I realised my head was unconsciously moving up and down trying to bring the sign into focus!

I hope you get used to them soon. I find they take a couple of days to settle down again each time I get the prescription changed.

Bloody old age!

Michael

Mon, 18 Apr 2011 12:50:39 UTC | #616703

Gnu Atheist's Avatar Comment 16 by Gnu Atheist

Bullshit Flag.

There is a large disconnect here that has to be addressed. You have to understand that it is NOT possible to simply remove a visual obstruction, such as a congenital cataract, from a child who has been blind from birth and expect them to suddenly "see". Here is the reason: The occipital (visual) cortex of the brain is not yet developed at birth. It undergoes a vast amount of development in the first few years of life that is directly stimulated by the images it receives from normally seeing eyes. No images - no development. Blindfolding a newborn for the first year of life will leave him/her irreparably blind. Partially obscurring vision will proportionately impact visual development. (This is what happens with amblyopia.) The first decade is the critical period. The older a child gets without adequate visual stimulus, the less he or she can be expected to recover. What recovery does come will take months to years. By the time they are in their preteens, the chances of any decent visual development is minimal.

So how can they take these light-perception kids, already 14 to 17 years old and expect them to see anything so soon after their surgeries? I guarantee that what vision they have is woefully deficient. If they do manage some gross shape discrimination given the "resolution acuities" reported, they will have NO depth perception, no appreciation for color, shadowing, and other subtleties that a normally sighted person uses to discriminate 3-D shapes.

We're all reading this as if these kids were being taken from years of complete blindness to suddenly normal vision. That's not what this is - it couldn't be. Accordingly we should be careful about what conclusions we draw from it.

Mon, 18 Apr 2011 17:02:37 UTC | #616771

Lion IRC's Avatar Comment 17 by Lion IRC

I dont see how these results answer the question in the negative. The children had not encountered these unusual shapes before. The results -

  1. Look but not touch. Success in identifying. 90%

  2. Touch but not look. Success in identifying. ("Nailed it". Assume 90%)

  3. Feel first then look without touching. Still a success but no significant improvement beyond 90%

Now, the question was...

"Could a blind person, upon suddenly gaining the ability to see, recognize an object by sight that he'd previously known by feel?"

I thought the participants were expected NOT to be able to successfully match the actual physical 3D shape with something they had previously (in blindness) only known by a name assigned to the tactile object. But in all three cases the success rate was the same.

Doesnt the 90% success rate in #1 answer the question in the affirmative?

Mon, 18 Apr 2011 19:54:58 UTC | #616833

Lion IRC's Avatar Comment 18 by Lion IRC

Surely a blind person can imagine shapes (spatial and metric properties) using ideas which are independent of sight.

Example. Ask the blind person to contemplate the 3D imprint their shoe leaves in the clay as they walk in a straight line (the shortest distance between two points / least number of steps taken.) Then ask them to consider an alternate path of steps taken, this time walking a longer distance (an arc or a zig-zag / more steps taken) in the same clay starting and finishing at the same points as in the first instance.

Upon regaining their sight, the person would already have an understanding that a straight line took fewer steps (footprints) than walking in a circular arc.

Thus, it would be possible to deduce, by sight alone (and thought), which shape was which out of the two their 3D footprints had earlier made in the clay.

Similarly, sight alone is (should be) sufficient to understand the difference between the straight line formed from one side of a cube to the other and the arc which describes the path from one side of a sphere to the opposite side.

Mon, 18 Apr 2011 20:21:02 UTC | #616840

Scruddy Bleensaver's Avatar Comment 19 by Scruddy Bleensaver

Comment 8 by Anonymous :

Comment Removed by Moderator

Man, this 'anonymous' bloke gets a lot of his posts deleted. I wonder why he keeps bothering to post?

Lame joke, sorry. As you were.

Mon, 18 Apr 2011 20:32:12 UTC | #616845

DarwinLovesYou's Avatar Comment 20 by DarwinLovesYou

Interesting tangent: It may take formerly blind people some time to recognize a once-familiar object, but they will still smile and use facial expressions they've never seen before. So that supports the claim that we do have some sort of innate wiring when it comes to expression.

Mon, 18 Apr 2011 22:38:45 UTC | #616882

Sarmatae's Avatar Comment 21 by Sarmatae

Comment 1 by InYourFaceNewYorker

Interesting. I wish, though, that they would have explained how their sight was restored, and if these kids were blind from birth.

From the Participants and Procedures supplementary material. Restoration procedure with the birth reference, my bold.

Participants: Five subjects recruited from Project Prakash proved appropriate for our study. Subjects YS (M, age: 8 years), BG (M, age: 17 years), SK (M, age: 12 years) and PS (M, age: 14 years) presented with dense congenital bilateral cataracts. Subject PK (F, age: 16 years) presented with bilateral congenital corneal opacities. Subjects received a comprehensive ophthalmological examination before and after treatment. Prior to treatment, subjects were able only to discriminate between light and dark (diagnosis: PL), with subjects BG and PK additionally able to determine the direction of a bright light (PL/PR). Given their profound occlusive pathologies, none of the subjects were able to perform form discrimination to attempt any of our tests of higher level visual function. YS, BG, SK and PS underwent cataract removal surgery and an intraocular lens (IOL) implant. PK was provided with a corneal transplant. Post-treatment, subjects YS, BG, SK, PS and PK achieved resolution-acuities for near viewing of 0.24°, 0.36°, 0.24°, 0.54° and 0.24° of visual angle respectively (assessed using Landolt C patterns; subjects indicated the gap by pointing to the gap directly or to the direction of the gap relative to the C).

All subjects were drawn from rural areas in north India. Although their parents noticed their visual impairments at birth (both via the lack of visually directed orienting behaviors as well as the manifest whiteness of the pupils or corneas), none of the children received treatment because medical facilities were not available locally and the families could not afford care in city hospitals. They were identified as candidates for treatment during outreach sessions for pediatric ophthalmic screening. The field-based screening was followed by a thorough ophthalmic examination in the Shroff Charity Eye Hospital. Using direct and indirect ophthalmoscopes, slit lamps and B-scan ultrasonography, this examination assessed ocular pathologies in anterior and posterior eye segments and was undertaken in conjunction with standard tests of visual function using Lea charts. For the cases described here, the pathology was confined to either the lens (YS, BG, SK and PS) or the cornea (PK) and bilaterally obviated all form vision.

Tue, 19 Apr 2011 09:59:38 UTC | #617037

njwong's Avatar Comment 22 by njwong

Comment 21 by Scruddy Bleensaver :

Comment 8 by Anonymous :

Comment Removed by Moderator

Man, this 'anonymous' bloke gets a lot of his posts deleted. I wonder why he keeps bothering to post?

Lame joke, sorry. As you were.

You reminded me of this one:

Every 8 seconds, a woman gives birth to a baby. We must find this woman and stop her!

Tue, 19 Apr 2011 13:23:33 UTC | #617074

reebus's Avatar Comment 23 by reebus

I wonder what an fMRI would reveal in the before, and after and later?

Wed, 20 Apr 2011 08:41:28 UTC | #617375

God fearing Atheist's Avatar Comment 24 by God fearing Atheist

I've just found a TED talk about this project. I think it is more interesting than the OP article.

Wed, 27 Apr 2011 21:07:18 UTC | #620074

SecularMinded's Avatar Comment 25 by SecularMinded

I am deaf, and I have often wondered if in the event I gained perfect hearing if I would be able to recognize spoken words.

Mon, 27 Jun 2011 20:57:12 UTC | #843559

SecularMinded's Avatar Comment 26 by SecularMinded

I am deaf, and I have often wondered if in the event I gained perfect hearing if I would be able to recognize spoken words.

Mon, 27 Jun 2011 20:58:50 UTC | #843560