Neurons in human skin perform advanced calculations
medfak.umu.se
medfak.umu.se
I usually carry too much junk in my pockets, and when I dig around in my pocket for something it amazes me how fast I can recognize what I'm touching. I don't know why but I've thought that there is some other non-conscious system in place that, at a minimum, helps improve tactile recognition. It's kind of subtle, but it feels like my hand somehow knows what I'm searching for, and can recognize it much better than I can.
Also, along the same lines of thought, I suspect that there must be a whole lot of intelligence locked away in our bodies that isn't easily accessed consciously, but it's still there.
As a thought experiment, lets say a famous guitarist loses an arm and gets a perfect transplant or a prosthetic which perfectly matches their previous dexterity. Would it perform as well as their old hand, or was the hand performing additional calculations on incoming and outgoing data that could never fully be replicated by a replacement.
Now take it a step further and assume a random person receives a famous guitarists arm in a perfect transplant. That arm is an instrument in itself with its stored knowledge, but that doesn't mean the receiving brain knows how to communicate effectively with it. I'm sure they would have basic communication, but the extended neural vocabulary of the old Brain-hand pair would be known to the new host-brain.
Personally, I believe it is a tandem effort between CNS and PNS in which each becomes accustomed to the signals sent by the other.
For example: A brain tells a finger to curl HARD, the finger neurons receive the brains input, modulates it with local factors, and sends it to the muscle. Likewise, the finger knows the feel of the strings exceptionally well, and can send highly detailed messages back to the brain who is used to receiving highly detailed messages. But in the new host who doesn't know this advanced feeling, it just feels like a regular old input.
You may or may not have seen the recent discussion about the "gut brain" and how it influences mood.
Most brain processes are subconscious, so if neurons outside the brain perform part of those processes, it should not really matter. Subconscious processes are subconscious, within the brain or not.
Anyways, read "On Intelligence" by Jeff Hawkins for a theory of how very fast pattern matching works in the brain. Skin neurons not needed, but can also fit into the theory I think.
http://en.wikipedia.org/wiki/Amphiprioninae#mediaviewer/File...
it feels like my hand somehow knows what I'm searching for, and can recognize it much better than I can
Imo that is just your brain having learnt your habits in such a way that you now don't actively have to think about it anymore. The sensory inputs of your hand still go to your brain, and are processed there into commands to your hand's muscles. Subconscious or not, sensory input locally 'pre'processed or not, your hand is not locally processing that complete cycle so it doesn't 'know' anything nor is it working standalone.
The other major reason is that much of cognition happens outside the body, in physical and cultural structures that are even less computationally tractable.
I think you should look at the numbers some more before issuing confident proclamations like that: the brain has something like 80 billion neurons. The famous gut has more like 0.1 billion neurons, the heart has more like 0.0004 billion neurons, and one's skin isn't going to contribute that much. The number of neurons outside the brain is much much less than the uncertainty in current estimates of how many neurons are in the brain - they're just not an issue. If one can compute something approaching the brain, then one can certainly handle the rest with a spare 1% of capacity or so.
Likewise I think the idea of "uploading your brain" is ludicrous unless the plan is to simulate it existing in a virtual physical world. The human brain reacts poorly to sensory deprivation - consciousness dissolves in the absence of physical sensory input. Cutting off every sense totally? I don't think we have any evidence to suggest that what would remain could qualify as a human mind. And we've got some evidence that it would not. Our bodies and our brains are not separate. Dualism is fundamentally untrue. We can see this in many studies of various injuries that rob people of various capabilities of their body which bleed over to significant effects on their mind. Make people hold a pencil in their teeth, which forces them to 'smile', and they will have more positive emotional reactions. People with paralyzed facial muscles suffer decreased emotional range in their mind. Paralyzed individuals generally experience depression (separate from the depression expected from suffering harm). Cutting off the brain from the body hurts the mind.
For one, study of brain increasingly points to widely distributed circuitry as the way functionality is implemented. But the brain doesn't exist isolated from the rest of the body, on the contrary, endocrine, immune, gut systems are highly interconnected with brain circuits.
IOW it's plausible neural circuits throughout the body are part of the brain's distributed circuitry, and contribute to functions we identify as "brain functions". The idea of "brain" as synonymous with "brain function" may be a great oversimplification.
The second idea might support a concept of body-wide distribution of information processing circuits. In embryogenesis, brain and skin both stem from the outer layer or ectoderm of early embryonic development.
We can speculate this common origin means neurons in the skin, and throughout the nervous system, are endowed with computational capability and continue to participate in non-local computations. This idea implies neurons winding up at locations far from the brain could still be included in the distributed network.
It will be interesting to find out where the research on neurons in fingers takes us. It might turn out to be a wild ride.
The problem in Parkinson's is degeneration of midbrain dopamine neurons which project to other brain regions that regulate and coordinate body movements. It's hard to imagine what connection would exist between neurons in the skin and the dopamine neurons in the brain.
That's not to say the skin's neurons aren't amazing in their own right. Very interesting research indeed.
Available here: http://rifters.com/real/Blindsight.htm for anyone interested in a great sci-fi read.
... my issue is whether or not that ought to be called "calculation" or "computation." sure it's an /interpretation/ of the natural process, but not necessarily equivalent. I realize that's not what this article is saying, but i wonder if we're getting too bogged down in algorithms with some of these things.