Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 


Forgot your password?
Close
typodupeerror
×
Science

Use All Your Brain, Not Only Neurons? 75

Posted by emmett from the more-science-questions dept.
SEWilco writes: "Iowa State researchers found evidence that glial cells communicate in the brain. Previously it was thought that the neurons were active, but glial cells were only structural and nourishment objects. Apparently glial cells can influence neighboring neurons at least through glutamate signals. Details in the Proceedings of the National Academy of Sciences. Maybe we still have a little more to learn about biology." I know, it's my second 'science question' headline of the day, but heck, most science headlines should end with a question mark.
This discussion has been archived. No new comments can be posted.

Use All Your Brain, Not Only Neurons? More

Use All Your Brain, Not Only Neurons?

Comments Filter:

  • The idiots are out in force today! (Score:1)

    by Anonymous Coward
    I know that this post is pretty pointless, but the amount of pointless and uninformed comments and moderation on this topic is really annoying me. Already we've had comments such as "Will glial cells be incorporated into ANNs?", "The brain uses quantumn [sic] computing - are glial cells involved in quantumn [sic] computing?" and "I don't understand the topic, but I'm gonna post anyway". Anyone who has a reasonable grounding in neuroscience would realise how f*cking idiotic these comments are - but the moderators moderate this sort of drivel up.

    I know that biology isn't a mainstream Slashdot topic, so people's ignorance on the subject is understandable. But if you don't understand it, then please don't make a post about - there really is no need to broadcast your ignorance to the world. And the same applies to moderators - don't moderate it up if you don't understand what the post is getting at - you make the Slashdot community appear to be stupid, and annoy the hell out of those of us who are familiar with the subject matter.

  • Chmrr,

    The material that covers the axons of the neurons is myelin, not glial cells (see http://www.dictionary.com/cgi -bin/dict.pl?term=myelin [dictionary.com].

    Myelin allows the chemical-electrical transmission to happen in a more "productive" manner. Faster and better neurotransmissions from one neuron to the next.

    Glial cells are the support structure, but myelin is separate. Glial cells are not neurons. I guess now their finding that Glial cells do more than just support and can influence neurons cells in certain ways. If you ask me this isn't that extrodinary, because the more glial cells you have around the neurons, the better off things are so its obvious the glial cells influence neurons in some way. I guess we're just getting more knowledgable about how.

    Maybe by the time I get this post in someone will have explained it better but I'll add my 2 cents anyways and expand on Chmrr's explanation. The computer mouse analogy works well. The mouse is a neuron. The big plasic chunk is the body of the neuron, and the tail is the axon. On the body are little strands which extend out to "touch" the axons of other neurons. When the neuron gets enough impulses from other neurons through the little strands (called dendrites) the neuron body fires a charge down the axon (mouse cord) off to one other neuron.

  • Do you think that a head in a jar would think in the same was as when it was attached to the rest of the body?

    If the head had grown up attached to a body, the basic thought patterns and capacities would be similar, though would change in ways similar to those who grow up normal, then become quadraplegic through accident. A head in a jar (BIV for you h.p.o readers) raised that way would likely think in very different ways, though.

  • " I'd like to know if there's evidence that glial cells also have functional calcium uptake pumps and if their level of calcium fluctuates with blood level or remains constant..."

    Glial cell (C6 glioma) calcium levels fluctuate with that of the external medium. Changes of a few mM produce cytosolic changes on the order of 10's of nM (J. Phyiol. several years ago). In vivo...who knows?

    "While this is interesting news, it's certainly not true that we ever thought of glia as (in the
    words of the press release) "little more than glue." "......

    Before 1950, some researchers confused the extracellular space in the brain with glial cells. The 'space' was actually cellular.
    Unfortunately, glial electrophysiological characteristics did not, do not, lend themselves to sustained, fundable study. i.e., where's that action potential? This glial cell calcium story, and the many other glial calcium studies, may help change some perceptions.

    I agree with you: current thinking is astrocytes are good for you when you're developing your brain (providing pathways to guide neurons to 'final' destinations) but 'bad', if you're an adult who has a penetrating nerve-killing injury.

  • Biological neurons are extremely complicated. In fact Hodgkin and Huxley received a Nobel prize for modelling a giant squid axon in 50s. They used three partial differential equation to describe a simple neuron. And even that description was far from complete. In fact I don't think even now there is a realistic comprehensive model for cell interactions in the brain.

    Nobody knows much about their computational capacity or how they do computations and transmit information.

    Artificial neurons in neural nets are exceedingly crude approximations to the real thing.

  • What makes them more complicated? It seems to me that they just receive input, and, if that input meets a certain threshold in freqency (all nerve impulses have the same intensity), it generates output that is sent to whatever connects to it.

    I think that the neurons in our brains have many more connections to other neurons than most artifical networks; common artificial neural networks are arranged in layers, which reduces the complexity significantly. Also, no one really knows what learning algorithm the brain is using, therefore even a perfect mechanical simulation at the neuron level might not act much like a real brain.
  • Penrose is full of it.

    His reasoning goes as following:

    Thought process is a mystery to me and I want to belive that it cannot be described by a Turing machine. Well, let's substitute one mystery with a different one (i.e. quantum mechanics), which is not predictable and hence is not a Turing machine. I win.

    Wishful thinking coming from a respected scientist...

  • Huh? (Score:1)

    by ploeg ( 3058 )
    While I'm very happy that Jennifer Dukes Lee (who I met during my brief days at the Iowa State Daily) made Slashdot (go Jenny!), I'm not seeing the news value of a discovery whose significance was recognised "in a 1994 scientific journal called Cell." Just wondering about that.
  • Hi. Read this: http://www.kuro5h in.org/?op=displaystory&sid=2000/7/18/122257/231 [kuro5hin.org]. Please don't b-slap me; this is important!

    --

  • Offered by physicist Penrose who says "I'm too stupid to figure out the complexity of the brain, so I'll confound things with mumbo-jumbo physics".

    Before you jump to conclusions you should note that every system is a quantum system. That is the whole point of physics; a unified model of the universe. It's not like "an electron is a quantum system and an apple isn't".

    A similar argument is that quantum effects are only evident on a small scale or at low temperatures. The freakin computer you're using to read this shifts macroscopic amounts of charge in a way that can only be explained by quantum mechanics. See Nature, 406 p43 for an example of macroscopic quantum superposition.

    For the relationship between quantum computation and (classical) Turing machines see Deutsch, 1985 in Proceedings of the Royal Society of London 400 (pp97-117). It seems all that "mumbo jumbo physics" may actually play a role in this after all.

    To me it seems ridiculous and unimaginative to assume that even though QM is fundamental to the structure of the universe and seems intimately connected to consciousness (google: "Wigner's friend";"Schroedinger's cat";"measurement problem"), consciousness is strictly a classical phenomenon.

    Dave

  • The major foundation of science is that you can't make a real claim without some evidence to back it up and they simply never had the evidence to say these things.

    This is exactly the point. They had no valid evidence that suggested that neurons to not regenerate. If they did have evidence to suggest that, then by definition it's not valid "evidence" and their methods are severely flawed. If they didn't have evidence and just made something up, such as "well, it doesn't look like the regenerate, so we'll just say that they absolutely do not reproduce", which seems to be what you're suggesting, then they are not scientists by any stretch of the imagination.

    I recall very specifically of reports in text books, technical literature and even science shows on TV and in other mass media stating in very clear and specific terms that neurons do not regenerate. I believe I was even taught this in school. Since this is wrong, they must have had no valid evidence to base this on, and preferrably should not have spread lies to so many millions of people.

  • Learn to Image Stream [winwenger.com], a technique pioneered by Win Wenger, author of The Einstein Factor [amazon.com]. Image streaming strengthens the connections between the neurons in your head (or something like that..) I'm just starting to get the hang of it, but it's a neat process..

    Some other sites exploring maximizing the possibility of the human mind:

  • Seems to work fine on Futurama. :)
  • For years I heard that the brain *never* regenerates cells. The brain cells that you're born with are the only ones you will ever get. Now, it is known that is completely wrong. The brain does have the ability to regenerate brain cells that are lost.

    Well, actually the brain is rather odd in that it doesn't have the same regenerative capacities as the peripheral nervous system. A patient with brain damage never recovers fully. Sometimes new dendrites (branches) are formed by remaining neurons to help, sometimes the patient can learn other ways of completing the same task, but generally there is little regrowth of damaged tissue. However you are right in saying that new brain cells are produced (there are many theories describing the purpose of these new [and sometimes temporany] cells), however full regrowth of damaged tissues has not been observed.
  • Some speculate that some of the brain's functioning occurs at a quantum level inside of the microtubules inside of neurons (e.g., Penrose [amazon.com]). The notion is that quantum effects are necessary to tie the disparate processes of the brain together simultaneous, in other words consciousness. AFAIK, glial cells do not have microtubules so they wouldn't be involved in these proceses.

  • In very well controlled, scientific experiements, the parts of the human brain responsible for processing visual information have been found to activate few milliseconds before the actual light signal has been delivered to the eye

    Howsabout giving us a citation on that? I'm a bit sceptical about this, having studied cognitive science for the past four years and heard nothing about this magnificent, knock-down argument for quantum processing...

    That was bitchy. Sorry.

    /bluesninja

  • Einstein had twice as many glial cells... (Score:4)

    by kevlar ( 13509 ) on Wednesday July 19, 2000 @01:56PM (#920167)

    Its true, he had twice as many glial cells, and at the time of his death, nobody knew why or if it had an impact on his intelligence.

  • Glial communication (Score:3)

    by BWJones ( 18351 ) on Wednesday July 19, 2000 @11:52AM (#920168) Homepage Journal
    This should not be that sensationalistic. There has been speculation for quite some time now that glial cells do more than "hold stuff together"

    The major functions of glial cells have long been known to be "supportive" of the communication functions of neurons. To accomplish this, there are several types of glial cells in the central neurvous system (CNS). Some of them (Oligodendrocytes in the CNS and Schwann Cells in the peripheral nervous system (PNS) form myelin sheaths, which are insulative wrappings around axons that allow the axons to conduct information more rapidly and in isolation from each other to prevent cross talk. Other types of glial cells regulate the composition of extracellular fluids, assist neurons in metabolic activities, and participate in various humoral functions within the CNS.

    In development, glial cells provide critical support functions for neurons such as guiding developing neurons to the right places in the brain and at the right time as well as functioning as a storehouse for neurotransmitter precursors and energy reserves for active neurons.

    It has long been known that glial cells regulate the amount of neurotransmitter in the synapse by uptake of neurotransmitter and buffering of Calcium in the synapse as well which is critically important to synaptic release. Signaling in the CNS could certainly be influenced by the speed at which available neurotransmitter is taken up and also calcium. Many glial cells also have receptors for neurotransmitters and may play a role in the co-incident release of various traditional and non-traditional neurotransmitters or neuromodulators.

    It should also be noted that glial cells also play a very intimate role in the recycling of neurotransmitters such as glutamate, where they convert glutamate into other metabolites that neurons can use for metabolism or neurotransmission. This too can influence cell state and thus signalling.

    Finally there is some limited evidence on the electron microscopic level that there are actual synapses on neurons from glia. If true this indicates a more direct and speedy communication between glial cells and neurons.

  • I recall very specifically of reports in text books, technical literature and even science shows on TV

    Well, don't blame the scientists if the popularised science makes it all sound too clear cut. And regarding the text books, how do you think it would sound to an already bored high school student if the science books would endlessly speculate whether this or that theory is correct. People who write those books have to draw the line somewhere and call the present knowledge as "the truth". The strong stuff (=the fact that in reality we know very little about anything) is left to those who decide to pursue a scientific career.

    I am a professional scientist. For every answer I get from my research, there are always more questions. It just never ends and you can never be sure.

  • Myelin sheath actually consists of Schwann cells, which are wrapped many times around the axons of the neurons. Schwann cells are classified as glial cells.

    I remember Schwann cells contain a lot of fat, which is white. I'm not sure why - might be that fat is a good electric or chemical insulator. The white-gray colouring of the brain is their product (neurons are gray); very long axons connecting the gray cortical regions are covered by myelin sheaths, to increase the speed of the transmissions.

  • Not enough hours in the day, so maybe this will compensate
  • No kidding. I just got done with my med school neuro class and we had a seminar on how glial cells are responsible for all sorts of things, including ionic balance, nerve regeneration, rapid uptake of secreted neurotransmitters, and, yes, even communication. It always seems that whenever the media pays attention to a science topic, they like to say things about how it opposes conventional wisdom. I'm not sure what that accomplishes, though. I guess they just like scientists to be wrong...

    Invicta{HOG}

  • Re:Huh? (Score:1)

    by Watts ( 3033 )
    Journalistic integrity from someone who has worked at the Daily? What the hell is the world coming to? I thought the entire purpose was to create fairly mainstream articles that the overly conservative student body would be shocked by!

    But seriously, we need some sort of slashdot review board for this sort of thing. Or the editors need to at least search slashdot for past articles in the same vein, read the actual article linked to, and *then* post an article. A review group would be able to do follow-up research, later clarifying or adding to the article.
  • It wasn't quite twice as many, but there were definitely more. See more info at http://faculty.washington.edu/chudler/ ein.html [washington.edu]
  • There are several journal articles and books that explore the effects of indirect neuron-neuron interactions, including glial cells.

    This is all a part of a growing belief that while the "direct" interactions are the most significant, the indirect actions, such as electrical fields generated by groupings of neurons are significant in the brain's operation.
    And, yes, there are connections between glial cells and neurons, they act, acording to many articles like the bases of transistors, altering the intensity of a neuron's impulse.

    Also, since we are mentioning complex methods of communication within the network, the interactions of dendrites (the "outputs" of the neurons) can have suprising amounts of influence on each other in a so called dendretic network, a
    minor neural environment at the end of each neuron.

    Basically, as time and our knowledge of the brain
    has increased, we see that building a brain in
    a box by simulation isn't about big hardware alone. It is about understanding how the brain is a marvel of engineering and that we have a long way to go, no matter what catchy TV commercials say.

    The following journal articles/books might find
    some interest:

    Koch, C., Poggio T., & Torre, V. (1983). Nonlinear interactions in a dendritic tree: Localization, timing, and role in information processing.
    Proceedings National Academy Sciences USA, 80.

    MacLennan, B. J. (1992a). Field Computation in the Brain (report CS-92-174). Knoxville TN: University of Tennessee, Computer Science Department.

    MacLennan, B. J. (1992b). Information Processing in the Dendritic Net
    (report CS-92-180). Knoxville TN: University of Tennessee, Computer Science Department.

    Shepherd, G.M. (1988). Neurobiology, Second Edition.
    New York NY: Oxford University Press.

    As for software implications, not soon since there are not very good mathematical modeling systems to even start exploring this aspect of neural interactions. Plain old artifical neural networks (with their own variations of interest) will still be your best bet for betting on stocks.

    Michael Campfield
    Computer Science Department
    University of Tennessee, Knoxville
  • Actually, they had gross evidence about neuron growth. Wounds to the brain (and the spinal cord) do not repair themselves the way many many other body parts do. Well, now we know there is some repair ability, although there are limits on large-size repairs -- particularly as it's complicated by neuron/axon deaths and scar tissue.
  • There's a quite interesting couple of pre-prints in the arXiv [arxiv.org] dealing, in part, with the similarities between quantum logic (not quite the same thing as quantum computing) and cognition. (And don't forget that pre-prints can range from pure nonsense to wonderful - I'm not clever enough to tell where these particular ones lie on that spectrum)

    arXiv.org/abs/quant-ph/0007044 [arxiv.org] - We show how Bell inequalities can be violated in cognition, specifically in the relationship between abstract concepts and specific instances of these concepts. This supports the hypothesis that genuine quantum structure exists in the mind.

    To even vaguely understand the above, you'll need to read:
    arXiv.org/abs/quant-ph/0007041 [arxiv.org] Why the Disjunction in Quantum Logic is Not Classical
  • It has been speculated that quantum computing effects may occur in the brain. However, as I understand it, the current conventional wisdom is that such effects are minimal at best, and do not impact on the overall result of brain function.

    Unfortunately, we will never know until we take a very smart person and run their brain through a particle accelerator and watch the effect as it smashes into a solid block of steel. Any volunteers?

  • wow... a rediscovered kind of First Post (literally)!

    If this theory is true, apendicitis (sp?) would be one heck of a migraine ;-)

    It's very unlikely though... our brain is very well protected from external factors of most kinds. On the contrary, our guts are very close to huge sources of infection, and not strongly protected.

    My guess is that we have to be very carefull with all the shit that goes trough there, so, it's highly monitored to raise the alarms asap if needed.

  • If the brain didn't regenerate its cells, we would all be brain dead from stress already. So all those neuron scientists can go kiss themselves. And how much of our brain is glial anyway? If it's about 20%, I might pay a little more attention.
  • Thanks for the interesting reply. Of course it was foolish of me to say that we never thought of glia as inert...

    current thinking is astrocytes are good for you when you're developing your brain (providing pathways to guide neurons to 'final' destinations) but 'bad', if you're an adult who has a penetrating nerve-killing injury.

    Funny how often we have to fight against the fruits of evolution when trying to do unreasonable things like transplant organs, travel in microgravity, and live 140 years...

    - Michael Cohn

  • The microtubules argument of Penrose has been multiply rebuffed since it was first proposed, at least based on what I've heard. I'll try and dig up the synopsis from my copy of Beyond Humanity and post it.

    You owe the Zombie Oracle a slice of Broca's brain. ARrrRRRgh pick-uhled braaaaainsARrrrGHhh.

    -TBHiX-
    http://www.brains4zombies.com [brains4zombies.com]

  • aw come on, that's not fair.

    the fact people are thought stuff in school is not because the teacher happens to be an all knowing god with perfect knowledge of whatever he mumbles.

    I'd have expected a little more nuanced view from a scientist like you. You know as good as the next guy that someday someone is going to ask 'why' and 'how' in some area, he tries to understand it, builds a new theory, and then maybe things move on, even if your first idea is way off-target. Don't forget that science is in no way whatsoever a mechanical straight into the new goal. It's a big excursion with questions and idea's floating around.

    I was told at school that allmost any cell in c can allways regenerate, but due to specific factors, some are more apt then others. It had to do with the environment in which a cell resides, evolution of certain hormones, etc.. but I'm no biologist, so I'm not going to burn my fingers here :)

    maybe the neuroscientists were dead wrong, yes, but hey, it took, what, 13 centuries to notice the earth not being flat at all ?

  • The main problem is that what you hear in the popular press does not convey all of the uncertainties and caveats of the scientific literature. So a statement along the lines of "There is no clear evidence of neuronal regeneration in adult mammalian brain" becomes "Neurons can't regenerate." Of course, this was not merely an assumption--people had looked for regeneration and failed to find it. But absence of evidence is not evidence of absence. If you fail to find something, it may be that you are looking in the wrong place, with the wrong method, or simply that your technique isn't sensitive enough. And in fact, there was some evidence that occasionally new nerve cells might be "born;" it just wasn't very convincing evidence. And it was known that neurons regenerate in certain brain regions of certain birds, and in olfactory epithelium, so it clearly wasn't an absolute impossibility. So the latest results simply provide evidence of something that a lot of people suspected before, but couldn't prove.

    The glial story is similar. It's been known for years that glial cells have neurotransmitter receptors and that they can release neuroactive substances, so a lot of people suspected that they play a role in neurotransmission. They just couldn't prove it, because most of the effects observed were either small, or required somewhat extreme conditions. The new report comes closer to demonstrating that glial neurotransmitter release can occur under physiologically relevant conditions, but it probably won't convince everybody. The real skeptics will insist on direct evidence that this glial function actually plays a role in neural function--perhaps by somehow knocking out this glial feature and demonstrating some kind of cognitive deficit.

  • AARrrgh Arrrgh brains good! AArrrrgh Glial cells add flavour. Arrrgh.

    -TBHiX-

  • Hmm, most Neural Network models are based around a series of interconnected neurons. I wonder what impact this new discovery might have on them - maybe with glial cells modelled in software, and some hairy mathematics, our neural nets might become more powerful?
  • I didn't flunk biology, but I still can't decipher what they heck they're talking about?! I'm sure others on slashdot may be in the same position. This definately sounds interesting, though.

    kick some CAD [cadfu.com]
  • It's been speculated heavily that the brain uses quantumn computing, for various reasons. Could these glial cells be involved in quantumn computing?

    How do we get these glial cells to communicate with the airport antennas on my new G4 Cube so I can use my brain as a processor?

  • assumptions (Score:4)

    by PD ( 9577 ) <slashdotlinux@pdrap.org> on Wednesday July 19, 2000 @11:02AM (#920189) Homepage Journal
    Does it occur to anyone that neural scientists are making too many assumptions?

    For years I heard that the brain *never* regenerates cells. The brain cells that you're born with are the only ones you will ever get. Now, it is known that is completely wrong. The brain does have the ability to regenerate brain cells that are lost. I was always skeptical and I was not surprised that the brain happens to do what every organ in the body already does. I think it would be quite remarkable if the brain was unique in that way.

    Now we find out that cells which the common wisdom classified as stuctural members turn out to actually have some communications functions built into them. I remember reading about this years ago, and I was skeptical about that too. At the very least, the structural cells would have *some* impact on neural activity, and therefore must be considered as part of the computational structure of the brain.

    I'm not sure where it's coming from though. Neural science draws from other disciplines, including psychology and medicine. One could argue that both of those subjects are still in the process of hacking their way out of their unscientific origins. I wonder if the half-completed scientific revolution in those subjects is hindering progress in understanding the brain.

    To be fair, artificial inteligence is also a contributer to neural science which is probably even farther in the dark ages than either psychology or medicine.

    Disclaimer: my wife is a psychologist. My comments are not meant as flamage, so if you're getting mad, contact me so I can clarify what I mean.

  • The article makes it sound like everything is in black & white. Those of us who are more experienced biologists know that it's really a gray matter.
  • No, this can't use quantum computing for the simple reason that they are on totally different scales. This uses chemical triggers (i.e. calcium ions) to stimulate the neurons. Quantum computers use electrons in different spin flip states to do things that simply can't be done in the regular non-quantum world, such as speed of light calculations. You can't do that with chemical transport because it relies on diffusion gradients to trigger an action potential.

    It's not really thought that the brain uses quantum computing, but rather massively parallel computing to do its work. This is that tactic taken by researchers of chemical computers. This doesn't really change the idea. What it does mean is two things that I see:
    • The potential to find the cause of many forms of mental illness, as the wrong neurons could be stimulated due to misfunctioning glial cells.
    • An increased potential for the massively parallel computing model for the brain. This provides extra dimensions for a brain to process information, making it more likely that this model is correct.

    All in all, this is pretty cool, although it might not mean anything. Just because you can get the cells to trigger neurons by making thenm release calcium doesn't mean they do this normally. All cells have calcium ions in them, the question is do the glial cells release them under normal conditions? That's what really needs to be investigated at this point.

    "I may not have morals, but I have standards." - Marcin
  • The article makes it sound like everything is in black & white. Those of us who are more experienced biologists know that it's really a gray matter.

    <BigBlockMopar slaps Kailden around with a large, partially-rotten trout.>

  • Parts of the brain long viewed as little more than the glue that holds neurons together might be more important than we think.

    So does this all mean that we should sniff more glue?
  • Hrmm.. Maybe I'll see increased performance if I start using these. My hardware dates from the late 1970s and I'm always looking for ways to keep it up to date with the newer models.

    wish
    ---
  • sou duck yick!

    you suck dick

    bye

  • It's been speculated heavily that the brain uses quantumn computing, for various reasons.

    That's the problem with all the quantum models of cognition that I've ever seen -- it could be happening anywhere at any time. There's just no way to tell. The most precice I can recall Roger Penrose getting is "quantum events in the neuronal microtubules".

    My suspicion (completely unfounded, mind you) is that the glial cells serve to modulate neural firing, perhaps to assist synchrony between neurons. Recent models of neural computation use synchrony to "bind" neural groups representing different aspects of the same objects.

    But then, the abstract didn't appear to be in anything resembling english, and the news report was devoid of actual information, so who can say?

    /bluesninja

  • I heard somewhere that Einstein's brain had a lot more glial cells than normal, but at that time no one knew if that was a factor in his intelligence.
  • That was the funniest comment of the week! Why did I waste my moderator points on other, lesser comments?
  • These results from the in vitro experiments are apparently very preliminary and should be taken with a grain of salt.

    It should be noted that all cells communicate with nearby cells. This is an important part of our ontogeny (growth), and function. Therefore it's rather obvious that neurons communicate with glia cells at least somehow.

    It should be noted that the glia cells do not necessarily perform any neural computation:

    Whether this glutamate release pathway is used during physiological signaling or is recruited only under pathophysiological conditions is not well defined.
    "Pathophysiological" means "unnatural". Anyhow, it might be just signaling that guides how the neurons or glia cells grow (during our ontogeny or afterwards). The changes in activation of the nearby neurons might be just a side effect, although it would nevertheless affect their computations, if the glutamate is actually released at postnatal (after birth) age (I understood that this is not known).

    - A novice artificial neural networks researcher who knows only very very little about neurobiology

  • I get it. It's the electromagnetic radiation from the hardware, that stimulates the glial cells, leading to a cascade of neuronal responses, fomenting the neuromuscular chain reaction that culminates in hitting the BID button on E-bay. No wonder the economists couldn't figure it out. They only assume rational utility maximizers.
  • Offered by physicist Penrose who says "I'm too stupid to figure out the complexity of the brain, so I'll confound things with mumbo-jumbo physics".

  • I wonder if one day engineers (maybe even now, biological, chemical, genetic and people in the biometrics field) will be able to describe the brain's (or other organ functions) with Verilog or VHDL (or some description language)? That would be an impressive code.... if you can model that you couldn't you apply it to creating and debugging more complex and efficient neural networks and other AI sub-products?

    Yes it would be hard to do it now, but for a behavioral / abstract structural design, how much do we really need to know, to implement?. Anybody think there is a low level way to get it done withtin the next 20 years? I am terribly curious

    It would by a heck of a long way off but it would be interesting.
    Nuff Respec'

    DeICQLady
    7D3 CPE

  • Disclaimer: I'm in CA and live in NJ. Thus all my refereces for what I write below are ~2500 miles away. And as I get older my memory is getting increasingly fuzzy.

    I've not seen anything that says that the visual system activates before the visual signal is received.

    That said I've read about a brain processing effect that might be what the AC above is refering to. I believe a discussion of this phenomena is available in Daniel Dennet's Consciousness Explained.

    What I have seen is that there is ~.5 second (and this may be off by an order of magnitude) delay between the brain receiving a signal and acting upon it and our becoming consciously aware of it. No big deal so far. The big deal is that the brain fools with the timing to make us think that we were conscious of it when it was first detected. Effectively it back dates the time stamp of our awareness.

    Until there were experiments that clearly showed what was going on this generated claims of scientifically proven prescience.

    I wish I had the references to give a more complete explanation.

    Steve M

  • Neuron/Axon deaths?

    Axons are parts of Neurons. Correct me if I am wrong, but are you saying that even if the brain cannot regerate entire neurons, neurons can regenerate dendrites and/or axons?
  • What makes them more complicated? It seems to me that they just receive input, and, if that input meets a certain threshold in freqency (all nerve impulses have the same intensity), it generates output that is sent to whatever connects to it.

    I thought it was like a kind of combined Observer and Composite design pattern, in programming terms. :)

  • ISU! (Score:1)

    by delmoi ( 26744 )
    We rock!

    And lets just say, the uni's, um, 'lax' policy about their network is very nice. ISU student's don't even need napster.

    Ok, let me try to make this ontopic... The artical said that the glial cells influince 'surounding' neurons, not neurons connected to it. I wonder if the techniques used by the glial cells can be used by artificial systems so that all we have to do is put stuff in the brain rather then actualy make nuruon connections. Of course, I have no clue, since I know nothing about nural biology.

    We don't know how bad things are in north korea, but here are some pictures of hungry children. -- CNN

  • Do you think that a head in a jar would think in the same was [sic] as when it was attached to the rest of the body?

    The short answer is yes. If the brain is still intact and provided with the proper nutrients, oxygen, etc. it should function no differently then before.

    The lack of a body will mean the lack of any stimuli from the body. Thus the brain's 'intuitive senses' (i.e. 'gut feel') will no longer have any effect on the output of such a brain.

    This seems similar to someone losing their hearing or sight. They still think the same way they just don't have as much input to use to think with.

    Thus the correct way to think about a head in a jar is as a severely handicapped individual. And no doubt the personality of that brain would change over time. (But that's true of all brains.)

    Since you said head in a jar I assume you mean that the eyes, ears, nose, mouth are still intact and functioning. If not, then we have the absense of these inputs, but the brain would still function the same way. But it would have no input to operate on. Sensory deprivation studies have shown that brains will create their own inputs, aka hallucinations. The person associated with that brain, experiencing massive sensory loss would probably go insane.

    Steve M

  • Oh man, Schwann cells.... that brought back a flood of memories of final exams - biopsych. Yuck. Well I guess if Schwann cells are classified as Glial then myelin can be classified as glial. I guess when someone says Glial cells, the first thing to come to mind isn't Schwann cells. I guess between the 3 of us we're getting somewhere.
    But this whole notion of "Use All Your Brain, Not Only Neurons?" (from the /. article title) is news is kinda silly. Of course we use our whole brain. It is a whole system. Each part is pretty necessary.

    (Biopsych finals... hmmm. I'm glad I work now. ;) Fun subject, but the trick question exams sucked.)

  • I don't think this is a fair claim. All science is limited by the evidence at hand. Neuroscientists looked very very hard for things like regrowth of cells, only they simply didn't have the evidence to support that they can regenerate. The major foundation of science is that you can't make a real claim without some evidence to back it up and they simply never had the evidence to say these things. There was never evidence to show that glial cells could potentially support communication rather than just insulate (which is a critical function in itself, precluding the need for the cells to facilitate communication directly) and now there is.

    Science marches on. You don't know something. You look some more and you learn something. That's how it works. Can you honestly say that physicists didn't make any assumptions when they claimed Newton's Laws were absolute? They didnt' because there was no evidence to contradict it until Einstein came along and said it was relative. Don't blame science for its self imposed limitations, because that's what makes it work.

    "I may not have morals, but I have standards." - Marcin

  • Probably other cells are used too... (Score:3)

    by StevenMaurer ( 115071 ) on Wednesday July 19, 2000 @11:15AM (#920210) Homepage

    Probably in a few years scientists will find that intestinal cilia are used as well...

    That's why so many people have shit for brains.

  • The brain is one of the very few muscles in our bodies that we know don't know alot about. This an imporatnt discovery it helps understand how we think are how we use uour brain it might help us solve those great puzzles like why can't I pat and rub my belly at the same time

    If your brain is, indeed, a muscle, it's easily understandable how you might be unable to pat and rub your belly at the same time.

  • Most artificial neural networks (ANNs) model the biological neural computation only in a very abstract way. This abstraction is "computationally complete" and can thus model practically any kind of neural or non-neural computation, including the communications behaviour of the glial or any other cells. Excluding the very very hypothetical (and in my opinion unlikely) quantum computation.

    One should note that biological neurons are very complicated things, when compared to most artificial neurons, and their computational capability is much higher. Simulating them with typical artificial neurons would require a lot of them. But then again, we don't really know how efficiently the biological neurons process information, and it is very difficult to say if they are even as efficient as the typical artificial neurons.

    - An ANN researcher, although my knowledge of biological neurosciences is rather limited.

  • It has been speculated that quantum computing effects may occur in the brain. However, as I understand it, the current conventional wisdom is that such effects are minimal at best, and do not impact on the overall result of brain function. The reasoning behind this is that in a given cell, the gross chemical reactions that govern how a neuron will react are extremely predictable phenomena, keeping it out of the purvue of quantum effects.

    Some of the research I've seen in regards to the quantum effect applied to reasoning appears to be directed to sensory phenomena, i.e. the idea that two people observing the same phenomena (say, watching a tree get hit by lightning) do not register the event in the same way because (1) the photons from such an event are governed by quantum effects and (2) the neural matrix formed in a particular brain tends to be a dynamical one, that is to say, governed by chaos theory as opposed to quantum mechanics.

    A somewhat dogmatic but interesting discussion of quantum thinking theories can be found in a book called Beyond Humanity (subtitled something and the evolution of cyberminds. Just in case you're interested.

    We now return you to your regularly scheduled zombie-fest....AARRrrghh arrrgggh BRaaIIIIns!!! (And to think I made my first first post with such silliness! ;P)

    -TBHiX-
    http://www.brains4zombies.com [brains4zombies.com]

  • "just glue?" P'shaw! (Score:5)

    by laborit ( 90558 ) on Wednesday July 19, 2000 @11:23AM (#920214) Homepage
    The experiment involved artificially increasing levels of calcium in astrocytes (a type of glial cell) while monitoring adjacent neurons for signs of response to released neurotransmitters. Since the levels of calcium required were comparable to those found in the natural environment, the researchers concluded that glial cells may control neurotransmitter balance in the brain as well. I'd like to know if there's evidence that glial cells also have functional calcium uptake pumps, and if their level of calcium fluctuates with blood level or remains constant. Unfortunately, reading the full article requires a paid subscription...

    While this is interesting news, it's certainly not true that we ever thought of glia as (in the words of the press release) "little more than glue." Glial cells produce the myelin sheathing that allows motor signals to travel rapidly from the brain to the extremities, and their signals are important to laying down the organization of different areas in the early months of brain development. They're also an important adversary when it comes to repairing nerve damage in the periphery. Severed nerves actually try to grow back along their established pathways, but the glial cells poison them (presumably to prevent inappropriate overgrowth). Learning to inhibit this process may be the key to restoring limbs that are paralyzed.

    - Michael Cohn
  • Else we'd put legs on our automobiles and
    feathers on airplanes.

  • The Win Wenger/Project Renaisance page is actually *not* hosted by slashdot, but is at http://www.winwenger.com/ [winwenger.com].. Win Wenger's written 48 books, many on the nature of intelligence. I've only read The Einstein Factor, but found it very interesting. Based on his 35 years of research, he claims that anyone can raise their I.Q. by 20 points in 25 hours.. If it worked for Einstein, it can work for me, right? Anakin's Brain [anakin.com] has the full text of two of his books in the Project Renaisance [anakin.com] section..
  • Uhh no, it's Neurons, I don't know where you learned to spell it.
  • That is, they also metabolize/"mop-up" chemicals released by neurotransmitters. This is a general application of "Garbage Collection" in the technical sense; by re-allocating disused resources the GCs are doing hardware-based GC for the brain.
  • Picture the neuron as a computer mouse. (no, no wireless mice -- it messes up the analogy) The actual "mouse" part is the head of the neuron, and the cable is the long axon leading off from it. The rubber around the wire in the cable is the glial cell. Actually, the glial cell is shaped more like a fajita(sp?) -- really thin and long, but wrapped several times around the axon. These glial cells are actually a large part of the brain mass, so the discovery that they do something is fairly amazing. Anyways, hope this helps (love putting AP Bio to use.. ;)
    - Chmrr

  • I thought this looked familiar.

    Murphy TH; Blatter LA; Wier WG; Baraban JM.
    Rapid communication between neurons and astrocytes in primary cortical cultures.
    Journal of Neuroscience, 1993 Jun, 13(6):2672-9.
  • There's a book by Micheal D. Gershon called _The_Second_Brain_. He points out that there are as many connected nerves in the digestive system as there are in the brain and proposes that "gut feeling" is more than just a turn of phrase. (It's my first ever comment!)

  • You are quite correct. Neuroscience is still a very young field, and having taken a few courses in the field, I have read some fairly conflicting bits of research. As soon as anything even vaguely resembling a statement comes out, it is challenged. The real progress that is being made is in the details, for example, "how does our brain process olfactory sensory input," not by groups who discover something then use it as the basis for a sweeping generalization. [interesting digression] Some quite fascinating research has been going on in the olfactory field, incidentally - specifically in how our brains may be able to encode extra information onto a nervous signal temporally [nature.com] (free registration with Nature required to view abstract...) [end digression] However, speaking as a scientist, I wouldn't get my knickers in a twist over something like this until they come out with something a bit more concrete. The bulk of the real progress being made in this field is typically being made by groups of hard science types who rarely make mainstream press when they discover something. As for these folks: They mentioned the release of calcium effecting the neurons. we've known this for a while, and let me just say that soaking a cell in calcium has more of a sledgehammer effect than a scalpel. Of course, this could be a huge finding, but what it sounds like is that someone made an interesting discovery but has very little idea of what it actually means.

  • And in related news [theonion.com]...
  • Righto - microtubals are on the right scale of size for quantum effects. Almost every cell type has microtubes - they seem to be the basic scafolding of cells if nothing else - so any cell could "be involve with quantum computing".

    What's not been shown is does "quantum computing" take place in the microtubes, and if so how does it couple to the macroscale world.

    As for the glail cell paper - as they state it's not (yet) known if this effect is something that takes place under normal conditions or under abnormal stress.

    Note that "out of body" experiances generally take place under stress - near death, drugs suck as ketamine, breathing high levels of CO2 (don't try this at home - at take 30%CO2 70% O2 and it can damage you), and so on. If the effects seen are triggered by abnormal conditions around the cells, this might be an underlying cause behind the effects, explaining how the differing triggers can give the same result.

    I'd bet on the neuron modulation function as the most likely, given that the ion glutamte diffusion s are slower than neuron to neuron triggering. I'd agree that this may be one source of the bundling observed, groups of neurons being affected by the slower, wider area effect of the glia.

  • Or, as Francis Crick puts it, the body is the mind. Any mind/body duality is more religious hocus-pocus than actual fact. Do you think that a head in a jar would think in the same was as when it was attached to the rest of the body?

    ---- ----

Slashdot Top Deals

"If it ain't broke, don't fix it." - Bert Lantz

Close