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Comment by warkdarrior | Hacker News Reader

No, unless you replace your eyes with chips that perform the post-processing of the image.

Brain could certainly learn to do it :)

Maybe it can, but it doesn't do a thing. At least for me. Deconvolution of astigmatic eye lens image? Nope. Spatial superresolution by temporal integration? Nope.

Low-level visual processing in our retinas and brains seems to be too specialized to learn new tricks.

The brain does all the time spatial superresolution by temporal integration! Look up "saccade".

No idea about deconvolution, but I doubt computers can do better job identifying things from blurry images than brains.

Saccades are just compensation for low peripheral resolution and shortcomings of rods and cones. I had in mind getting more resolved images than what number of photoreceptors allows.

There are no "resolved images" that can be measured by pixels anywhere in the humans' visual system. Only talking about identifying things makes sense here, and that too, it is capable:

"Because the disalignments are often much smaller than the diameter and spacing of retinal receptors, vernier acuity requires neural processing and "pooling" to detect it."

https://en.wikipedia.org/wiki/Vernier_acuity

or use EVFs or hybrid EVF/OVFs in place of you glasses lenses. Could conceivably allow for AR glasses that would facilitate telescopic capabilities, once a million other roadblocks are overcome.

In a way our eyes ARE chips doing post processing. What is sent to the brain is heavily preprocessed.

I feel like our brains are like flexible a ASIC. They're mostly preprogrammed but do have some flexibility (neuro-plasticity).

I'm not under the impression that we could easily train the brain to follow some different, very specific, synthetic algorithm.

They're mostly preprogrammed. In what sense?

The various processing and encoding pathways in our brains have developed over millions of years of natural selection. You could think of human behavior as a "program" where each generation is an iteration on that program. Plasticity is part of that program: ancestors with neural plasticity that benefited them passed on those genes and thus "conserved" learning as part of the program.

This sounds handwavey. I read The Brain that Changes Itself and it essentially gave the opposite impression of what you are saying: the whole point of the brain is plasticity. People can see, balance or hear through nerves wired to their tongues, for example.

It's handwavey because many of the details aren't known, but what is known is complex and can't really be fit into a HN comment. Also I'm condensing what I know from everything I've read about biology. It's not quite accurate to say that the "point" of the brain is plasticity, and we can tell this by looking at organisms with simple brains and examining what their brain is used for.

Worms use their brain to identify and manipulate objects, to taste objects if those objects are identified as food, and to sense aspects of their environment including temperature and humidity. Bees use their brains to see, to fly, to communicate directions, and to coordinate various behaviors with other bees. There is very little plasticity in these simple organisms: a bee that can't communicate will not find a different way to do so, it will simply die.

As animals get more complex we can see that plasticity becomes more important. A bird needs more complex processing to be able to adapt its hunting strategies for different environments. If environmental changes force a bird to move to a new habitat, we can hypothesize that they are smart enough to adapt their hunting strategies to the new habitat.

The evolution of humans has involved many factors that would favor this kind of plasticity: roaming over diverse landscapes, predator spotting, group hunting, tool use, language, and social communities. The resulting large cerebral cortex that we have from these evolutionary trends also gives us the ability to re-wire sensory pathways in the way you pointed out. But when I say "brain" I think of much more than just the cerebral cortex.

Scientists agree that the Cambrian explosion caused an inexorable trend toward complicated nervous systems and I suppose therefore the initial flexible brain.

What I can't see evidence for is any notion that the brain was less flexible then became more flexible over time. Would it be incorrect to assert that it essentially began flexible, as a result of the appearance of nervous systems, and that's its primary property? Of course complexity increased with time. But did the flexibility also increase?

This is a fascinating question, and I don't think I'm qualified to give an authoritative answer to it, but I think the _primary_ property of brains and brain-like neural complexes is that they encode behavioral responses to stimuli.

Similar to how a signal transduction process mediates between molecular receptors on cell membrane and cell behaviors, the neural complex mediates between stimuli and response at the level of the organism.

But at the same time I can see why you are thinking about flexibility as some sort of "primary property" because they seem to be inherently flexible in some way. I'm locating _plasticity_ more narrowly to the cortex part of the animal brain, but perhaps the cortex is just an amplification of some simpler lower-level flexibility. At this point my knowledge of the subject falls short.

Edit: thank you for the interesting discussion, you have sparked me to dig more deeply into these topics!

Yep nice area to ponder. Maybe brains don't just encode behavioral responses to stimuli but rather allow pattern recognition. Cue the Gibson. :)

There are prima facie limitations to this, otherwise lobotomy victims would have naturally recovered.

Brains are bonkers at adapting. This upside-down glasses experiment is a good vision-based example:

https://www.theguardian.com/education/2012/nov/12/improbable...

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