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Comment by kovac | Hacker News Reader

I don't understand how these experiments lead to the conclusion separates higher cognitive functions from consciousness. I fact I don't see anything that necessarily she'd any light into the roots of consciousness here. Can someone explain how the results of the experiment lead to that conclusion? This looks to me like, if it were a computer program, encoding/decoding of the symbols seems to be messed up for a largely contiguous block of symbols. Like you get jumbled up weird shapes when you feed the wrong encoding to a program.

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I think RFS' loss is a little deeper than ablation of a contiguous block of symbols, since characters and numerals aren't likely to be represented sequentially in the brain they way they are on keyboards or ASCII. I agree with your conclusion otherwise. I see no connection to cognition in what the scientists explored.

Specifically, RFS' loss was specific to both encoding (recognition) and decoding (writing) of only those numerals that have no analogs among letters (not 0 or 1) had failed in RFS. Presumably this implies that the neurons that map the visual coding for numerals 2-9 in the cortex to and from their underlying concepts were lost. However the concept of each numeral persisted, so RFS could learn replacement glyphs and map them to the concepts, thereby using them as equivalents to numerals 2-9.

So I agree with you, this seems like only selective damage to the V2 or V3 portions of the visual cortex used strictly to encode/decode numerals 2-9. I too see nothing related to higher cognition or consciousness, at least in the early stage of RFS' disease mentioned here.

Methinks the author at Science Mag who summarized the work got a bit carried away in seeking cosmic revelations therein.

My understanding is he could see the numbers but failed to recognize or make sense of these pictures.He wasn’t aware of the letter pictures anymore and could not associate them with the “numerical symbols” stored in his memory (if our brains do it this way). But with the stored symbols he still can do mental math so his higher cognitive function must be at least partly intact. Using the computer program metaphor we can say his input routine for numbers is scrambled but the other calculation routines remained intact.

My guest is because we do math, our brain create the association for not only the numbers but also what we do with these numbers (maths routines). And because we don’t work with numbers all the time (we also can do symbolic maths), it’s necessary to separate the numbers with its meaning to accomplish these feats. If I would “program” our brain, it’ll be much more efficient to separate the recognition routines with the higher-function routines because we need to adjust the recognition routines all the time due the (slightly) different fonts and hand scripts of all the people.

That he could identity people, without being aware of it.

Basically, if there were faces inside a number, the EEG showed that his brain recognized the faces, but he did not know there were faces, instead he couldn't understand what he was seeing.

So the hypothesis conclusion from this is, recognizing someone's face happens separately from consciousness.

Basically, the experiment appears to show that your brain can recognize faces, without letting your conscience know about it. So you can't tell the face is there, but other part of your brain can.

But that seems fairly obvious, at least to me. Face recognition seems to be an extremely fundamental capability that has probably existed in some form almost as long as brains and image-forming eyes themselves. In RFS’s case, his brain’s ”face module” spotted the faces, his damaged ”number module” couldn’t converge to anything useful, and the jumbled mess for whatever reason overrode the faces in higher-level perception fusion processes. Possibly because the faces were so small so were lost in the noise, so to speak. Would be interesting to know how RFS would have perceived a face with small numbers drawn on it.

In any case, it is pretty well understood that our conscious visual perception is almost entirely unlike the raw stream of nerve signals emitted by the retina. We’re completely unaware of the huge amount of filtering, denoising, smoothing, stabilization, spatiotemporal fusion, extrapolation, interpolation, object detection/classification/conceptualization/contextualization/prioritization, and other processing that is done to create what we consciously perceive.

> But that seems fairly obvious, at least to me

There's many things that grow from prior knowledge as theories and hypothesis. So maybe from what we already know for the brain, you theorized that the conscious brain plays no role in recognizing faces, yet science needs to validate hypothesis with experimental proof. This is one such experimental data point that seem to validate that theory. I'm not sure we should start to dismiss the scientific process from what we consider obvious or not. Many prior "obvious" things were false, so obviousness isn't good enough in my opinion.

> In any case, it is pretty well understood that our conscious visual perception is almost entirely unlike the raw stream of nerve signals emitted by the retina

For me, the more interesting bit is more with regards to the limits of consciousness. In this case, it seems no amount of conscious effort trying to see and make sense of what you're seeing can actually unscramble what you're seeing. The experiment seem to indicate that the raw stream works as intended, demonstrated by being able to see the shape when rotated 90 degree, but that there is another part in the brain responsible for turning the raw shapes and colors into abstract cognitive information such as it being the number 8 or a face. And that this part is not controlled by consciousness.

Thus it shows that some high level cognitive tasks, like visual pattern recognition are seperate from consciousness. And this isn't something I would have necessarily assumed. Maybe I would have when it comes to really raw low level visual signals, like putting color labels to the wave length information of light, but when it comes to labeling an abstract concept, such as something being a number or a face, I'd have thought that some part of conscious thinking would be involved.

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