someone's studying cephalopod consciousness

monty

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:welcome: and glad to see you!

As usual, your thinking has me thinking as well... I hope we'll hear more on this from some of the other folks around, too.

I've gotta run some errands, but I'll be back with more comments soon, but I wanted to put out a quick thank you immediately, so here it is!
 

monty

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p.s. to try out the new "groups" feature, I created a ceph neuroscience "group" and invited a bunch of you. Unfortunately, TONMO isn't really set up to notify people of this sort of thing in an obvious way yet, and I'm not sure how having a "special interest group" will work, but I thought I'd mention it... I sort of like the discussion to be out here so anyone interested who happens by will participate, since the "elite group of neuroscience snobs" seems unnecessarily divisive... but maybe there are ways to say "notify the people in this group when a new post is made on a thread tagged as neuroscience or behavior related" or something like that... I haven't figured out what's available in the "groups" stuff yet...
 

monty

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I'll reiterate a "thanks," this is a great discussion (I really enjoy the early, creative parts of thinking through this sort of stuff!)

A few free-associative thoughts:

Another perspective similar to the "Neural Darwinism" sort of theme is in a book I read a few months ago: The Tinkerer's Accomplice by J. Scott Turner. As a physiologist, he loves systems, which he calls "Bernard Machines" (in contrast to "Darwin Machines") that are based on (often extended from) systems that use some sort of competitive interaction to maintain a balance, often homeostasis of some sort. For example, skin collagen involves a balance between cells that lay down fibers, and cells that remove them, so if the skin is cut, or stretched, it can compensate by changing that balance, possibly based on the stretch or cut direction.

Turner extends this idea to all sorts of things, including brains. I find that his explanations get a bit more dubious as he strays into neurophysiology, but I think they're great food for thought, and very similar to the observation that clones have different developmental nervous system connections, and that the brain constantly re-wires, in a sense, to be able to deal with new sensory information. I'm mentioning this because I suspect that looking at the brain-adaptation stuff from as many different perspectives as possible seems like a good idea...the "neural Darwinism" nomenclature is a good metaphor, but in some sense might be misleading, in that it isn't clear that there is anything like a genotype/phenotype distinction, and that the "survival" of connections isn't purely based on a fitness-type function... there seems to be more goal-directed and reinforced-success sort of a driving force, so maybe thinking of it as more Lamarckian than Darwinian is another perspective that's worth considering.

Turner takes this further, and suggests that nerve cells that fire too much are in danger of dying from "overwork," and that there is a system of homeostasis that arose for the "purpose" of keeping the nervous system from going out-of-balance in that way, and it had the side effect of making thinking computations more effective as well. So he believes that, for example, lateral inhibition could have arisen first as a way of damping out neural signals to where the cells don't over-excite themselves to death, and only after this was the mechanism used for computation. I'm dubious on one level: it's not clear that overexcitation is a problem until the cells are doing a useful computation, so I think this is more of an evolutionary constraint on the brain's available options to become "smarter," but I found it very valuable to be exposed to that as a perspective.

I also remember a neurobiology talk I saw sometime in the early or mid 90s, which involved some sort of small mammal whose offspring keep their eyes closed for several weeks after birth. It was determined that they had some system by which, while the eyes were closed, there were waves of "random" activity involving the retina and visual cortex (or maybe LGN or something) that seemed to be involved in "teaching" the developing eye and brain how to wire themselves... there was no visual input yet, but it allowed the brain's retinotopic map to correctly understand what parts of the retina were adjacent in preparation for receiving visual input later, once the eyes opened. I remember there were some details about the connection seeming "backwards" somehow, but not what they were... I know sometimes it looks like reverse-connections are important, like presynaptic neurons strengthening the synapse connection when the postsynaptic neuron fires, and this may have been an example of that.

I've become quite interested lately in control of development and homeostasis and how those produce the functional organism, since I've been annoyed (as a computer guy) for years that there are around 10^11 neurons in the brain and only 3x10^9 or so base pairs in the human genome, so it seems clear that the DNA can only specify a system to be set in motion that, quite robustly, produces a functional organization of the 10^11 neurons in the human brain, and all of the other systems of livers and lungs and toenails and earlobes. And where I agree with Turner is that, although teleology is a dangerous idea for the natural selection genotype/phenotype sorts of discussions of evolution, teleology, design, and other goal-directed lingo may be a good way to think about the systems expressed by the genes that actually actively try to help the organism meet survival and reproduction goals.

Of course, this whole comment is not directly related to the great idea of investigating how cephalopod brains' consciousness (or quasi-consciousness, or almost-consciousness, or "sophisticated behavior that we shouldn't jump the gun on and call consciousness") is produced and whether the anatomy has anything interesting in common with the analogous parts of vertebrate brains... it's just what I was thinking about when considering possible things to look for in cephalopod brains, and developing and dynamic comparative phenotype stuff in general.

I'm hoping that gjbarord will chime in here, too, since I see him as frequently in the "don't anthropomorphize or write too much into behavior" school, which seems like it sometimes also includes Hanlon, based on some stuff in Hanlon & Messenger. I've also caught Kat mentioning that :oshea: Steve O will thwack her occasionally for attributing too much teleology to things, but I'm not sure that's in a behavioral context...

Certainly, there's a lot of danger in being too anthropocentric in this sort of discussion, and attributing a lot of "human" attitudes to animals-- that's particularly relevant when asking questions about cephalopods, since although we're excited that there seem to be so many things in common between us presumably-convergently-evolved vertebrates and the "hey-we-got-here-first" cephalopods, there may well be ways in which the cephs took a different approach that has similarities and differences in terms of consciousness, self-awareness, emotion/reason differences, hormonal vs. neural signaling, and probably many other things I haven't thought of... certainly, cephalopods' neural control is a lot more distributed compared to our centralized brains, so that gross anatomical difference could lead to all sorts of differences in the ways they think... and cephalopods, since they have to control the chromatophores on their bodies based on visual input, have to have a very different sense of their own place in the visual world than most vertebrates. And it's also worth noting that modern cephs and fish have been co-evolving and competing for a long time, so it may have been advantageous for them to emulate each other's behaviors: maybe vertebrates' conscious brains only came about as a way to not be outsmarted by clever ammonites! But, of course, a lot of that was mentioned in the talk...
 
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Nice writeup, Monty. Sounds like it was a good talk, even if there were many parts that were over my head :smile:. The convergent evolution idea is interesting. It's strange to think that a ceph's brain can perform similar functions as ours when the makeup is very different.

I will come back to read the post just above me later... it is late and I wanted to read an article about cephs... after searching google for "octopus articles" (^^:wink: I figured tonmo would be a better place to find what I was looking for.

Anyway interesting stuff, albeit intimidating to the uneducated.
 

DWhatley

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If our brains are not "prewired", can we teach ourselves alternate "pathing"? hummm. In a minor sense, some people can learn to wiggle their ears (long out of fashion, I know, but it always made me wonder about teaching you mind to "find" the trigger to move muscles) or move other parts of their face that is generally not an on command movement. I have read that after a stroke, some people regain the use of what was lost even though the brain remained damaged. Perhaps we have other abilities we have not needed so they go undeveloped.
 

monty

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dwhatley;109210 said:
If our brains are not "prewired", can we teach ourselves alternate "pathing"? hummm. In a minor sense, some people can learn to wiggle their ears (long out of fashion, I know, but it always made me wonder about teaching you mind to "find" the trigger to move muscles) or move other parts of their face that is generally not an on command movement. I have read that after a stroke, some people regain the use of what was lost even though the brain remained damaged. Perhaps we have other abilities we have not needed so they go undeveloped.

Well, clearly we lack the neural "plasticity" that some animals have: a newt or an octopus can re-grow severed limbs and somehow get them re-wired so that their nerves work, even though their neural control systems are similar in complexity to ours.

Fundamentally, though, there are some traits where you either have the nerves or you don't... I don't know about the wiggling the ears, but I know that whether you can learn to roll your tongue into a tube has been shown to be genetic... if you don't have the right nerves, you can't do it. Perhaps if we understood it enough we could artificially induce new nerve growth (obviously it works when one of the abovementioned animals regrows a limb) but we don't know if it's even possible to re-induce a state that normally occurs only in embryonic development in adult humans... it's possible that the reason some animals can and we can't is that we gained some developmental advantage (like complexity) that had the side effect of losing that ability (like we can't turn on the regulatory system for some types of nerve growth without some sort of messing up the system like cancer.) But maybe our ancestors just lost it because they didn't need it, and if we understood it well enough we could "turn it on." I don't expect we'll have solid answers on this, let alone medical applicability, for quite some time, though, sadly.

In other news, people interested in consciousness from the philosophy direction might be interested in this, although I have to say I find it sort of typical of the things that I find not-so-productive about the approach philosophers have taken to consciousness and other "philosophy of mind" issues, which is part of why I found Dave's perspective very refreshing.
 

DWhatley

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Monty,
I still wonder if tongue rolling and ear wiggling don't fall within the rewiring ability. Some people find and use the muscles faster but I know it is possible to teach yourself to move your ears. I can't now but could a little with lots of work as a kid and probably could have learned to do it well had I continued to "train" myself. I also knew of a child (sibbling of one of my school peers and I witnessed the foot usage, not hearsay) that learned to manipulate his toes much like fingers and could hold a crayon/pencil and draw. The recent study that was able to induce new growth of a severed chick wing (granted, it was still in the egg and the control was difficult) suggests we my have not lost that physical ability (even cancer shows that cell growth can be changed) to redirect connections. I hope there is more work done with the idea of being able to change the wiring as it might also bring an answer to mental anomolies like sever depression or being prone to alcholism. I know they still use shock treatments with a lot of pain but some success (niece of a relative) which would suggest electical impulse disruption or repathing. Unfortunately, the possitive effects in this case are not permenent.
 

monty

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Ok, maybe tongue rolling is a bad example but there are certainly some things that can and some things that can't be "re-wired" readily in humans. For a lot of the neurological ones that can, V.S. Ramachandran has done a lot of good research and has written a lot of it up in popular science books. There are things, though, that are pretty clearly fixed in genetics or development... although I'll admit that some of the ones traditionally believed to be fixed aren't: a transplant patient recently changed her blood type to adapt to a new liver, for example.

However, in the class I'm auditing about gene regulatory networks, it's pretty clear that a lot of the parts that develop various organ systems and whatnot are controlled by the history and context of the cells, so there's never any situation where the right regulatory elements are turned on in an adult to create some organs or make some connections... so even if you had stem cells or something that could create new cells of some type, you'd also have to "fake" their history and put them in an environment that simulates they were in a 3 month old fetus instead of an adult or something like that.

In terms of ear-wiggling and tongue-rolling, if there *is* a connection to "find" then I suppose I agree that it could be "found," but if there is just no connection there, I'm not aware of any mechanism to grow a new one... I suppose one might imagine some combination of neurogenesis and laying down some chemical path to grow a new axon, but I think the peripheral nervous system's wiring is normally pretty well fixed... while in the brain there's a good deal of evidence for "plasticity" that allows rewiring.

I think the "reentrant" sort of stuff Dave talks about, though, is not so much about re-wiring, nor even the learning involving strengthening or weakening connections, but more about the ability to compare hypothetical or remembered models of the world to what's actually perceived.... to compare one's subjective "internal world" of ideas to the external perceptions, and use that for decision-making.
 

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