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Flying By Brain

Garabito writes "Scientists at the University of Florida made a living 'brain' by extracting 25,000 neurons from a rat's brain and culturing them inside a glass dish. Then, the neurons began to extend lines to each other, creating a living neural network between them. The dish had a grid of 60 electrodes connected to a computer running a flight simulator. The scientists were able to train the 'brain' to control the plane in the simulator and to react to conditions of the plane. Are we getting closer to create an artificially made conscious being, or perhaps, a living computer?" AlphaJoe was one of several readers to add a link to Wired's article on the experiment.

23 of 636 comments (clear)

  1. Re:Abby someone by ncurses · · Score: 3, Informative

    In Young Frankenstein, the guy is always saying, That's Frank (short o sound) en steen. In German, the second letter does get the sound, so it's ien, not ein. Unless you're talking about the original. Then it's Frankenstein.

    --
    Help! I'm being repressed!
  2. Re:Anyone know how it knows what is "good" and "ba by nucal · · Score: 5, Informative

    Steve Potter, the former mentor of the UF researcher has a pretty thorough description of it. http://www.neuro.gatech.edu/groups/potter/animat.h tml

  3. Re:Huh? by MoralHazard · · Score: 4, Informative

    I'll bite. No, this doesn't necessarily mean that a rat could be trained to fly a plane. A rat has millions of neurons, but most of them are taken up full-time doing specific things (strangely enough, a lot of that is scent processing). But if you can define goals for the rat, you can probably train it to do a lot of things, including a subset of the plane-flying challenge.

    You don't want to think of the neurons as "hardware" exactly, either. The process of building and training a neural network is about replacing the programming component of building a system, not about replacing the hardware. Writing a piece of software to fly a plane by itself is hard work--complicated task, not easily reduced to algorithmic instruction sets. Lots of tiny rule modifications needed to the basic set of "maintain altitude and heading". The trick with neural nets is that you set up the network, and then you train it by trial and error to do the task. It programs itself, essentially.

    We can and do build neural net simulations in pure software, which is where most of the research has been done so far. But neural net simulations on computers are VERY computationally expensive and take up a shitload of memory, so there are limits as to how big you can make your simulation and still do anything with it. This is a big problem, because neural nets can potentially do incredibly interesting things (like, say sentience!) if they get big enough--but we don't have computers big enough to model neural nets as complicated as we'd like.

    I know the article says that these guys are only using this project to investigate how neurons work in the real world, but the potential applications of this are big. Neural nets using actual neurons, not expensive simulations, could be cheap enough to build and train that they would find commercial uses.

  4. Re:working backwards by Shinglor · · Score: 5, Informative

    A brain is a neural network. Artificial neural networks were created to simulate them using mathematical models.

  5. Pretty neat, but by slobber · · Score: 3, Informative

    "If you think about your brain, and learning and the memory process, I can ask you questions about when you were 5 years old and you can retrieve information. That's a tremendous capacity for memory.

    I have to say, I don't remember much from when I was five years old. I remember where I lived and maybe can guesstimate where I spent a specific summer, but most of my knowledge comes from what my parents told me and from little "text" snippets that somehow got stuck in my head (for example, names of cities I visited, etc.)

    I can recall some images from the past, but I am not sure whether those are "true" memories or something synthesised by brain to "fill in the blank". This leads me to believe that human memory is rather lossy and large part of what I remember is just a rough approximation of what happened based on a few datapoints that brain actually remembers. Sort of like with people who have a defect in their iris - they still see an image in what's supposed to be a blind spot. This image is synthesised by brain to fill in the gap. Needless to say, occasionaly it turns deadly (especially while driving).

    --
    "You mortals are so obtuse." -Q
  6. Link to journal article by Ajae · · Score: 2, Informative

    A link to where the journal article can be found if you're sciefically inclined http://www.bme.ufl.edu/research/publications/detai lpublication.php?PUBS_id=10

  7. neurogenesis by Anonymous Coward · · Score: 5, Informative

    Well, neurons are living cells... ...and therefore they can reproduce. This is called neurogenesis...and as I understand it can be stimulated by appropriate amounts of neurotrophin and other chemicals.

    However, with all animal brains, there comes a point in the creature's development where the death rate is greater than the birth rate. In humans it happens at about three years, if memory serves (heh). If we could manage to find the correct chemical balance to maintain an average cell count indefinately, then perhaps we could devise a dietary supplement that would have the same (or better) effect on humans...

    Of course, giving a person a lot of neurons doesn't mean that person will make use of them...

    1. Re:neurogenesis by ebuck · · Score: 3, Informative

      Well, you need to do a little more research.

      Neurons grow and die all the time, and are not as "terminally differentiated" as you think. There's been a number of cases (even in humans) that provide evidence of these occurances, although not every portion of the brain supports neurogenesis.

      This behavior has been observed for years. See http://www.smithsonianmag.si.edu/smithsonian/issue s02/jun02/phenomena.html for a popularized article that's over two years old on this matter. Older articles exist referring to the phenomenon, especially in relationship to certain species of birds where a portion of the brain grows and shrinks in relation to the learning / forgetting of that season's birdsong.

  8. We already have brains in our abdomens by Anonymous Coward · · Score: 1, Informative

    The intestinal tract actually includes significant amounts of interneurons (the thinking variety of brain cells). Yes, you do think with your gut.

  9. Re:No Feedback Loop by synergy3000 · · Score: 2, Informative

    Why do you assume this is an organism? Neurons hooked to electrodes don't fit my description of organism. From dictionary.com organism is defined as:"An individual form of life, such as a plant, animal, bacterium, protist, or fungus; a body made up of organs, organelles, or other parts that work together to carry on the various processes of life" Alls I read are about neurons hooked to electrodes, nothing about various parts hooked together to carry out processes of life. A collection of neurons is very well powerful enough to "learn" how to fly. How do you think human pilots fly? Answer: With their large collection of neurons. Just as you can program a computer to fly a plane, you can do so with neurons. Whether this experiment is in fact doing that is another story since we don't have a good/full enough understanding of how the neuron processes work.

  10. Re:Do you have to think in Russian? by mchinand · · Score: 5, Informative

    I assume you're referring to this

  11. Bigger Problem is Growth of Novel Germs by reporter · · Score: 5, Informative
    Here is a reputable article about the use of pig brain cells in human brains. There is always the problem of an immune system reaction, but the bigger problem is the development of super germs that cross the species barrier.

  12. Re:Disturbing Experiment: Who is "I"? by leonscape · · Score: 3, Informative

    No its not. Whats commonly referred to as a lobotomy, is to remove or seperate the frontal lobes ( Higher functions ) and not seperate the two hemispheres of the brain.

    --


    If a first you don't succeed, your a programmer...
  13. Re:teh living computer by Hatta · · Score: 2, Informative

    It raises some ethical concerns as well...What would be this brain's level of consciousness?

    Negligible. You have more complicated systems controlling your blood pressure, posture, digestion, etc. Besides, by the time any actual technology develops from this research, we should be able to create neurons from immortal lines of stem cells.

    --
    Give me Classic Slashdot or give me death!
  14. Re:One question... by starm_ · · Score: 5, Informative

    Well I took a course about artificial neural net (not the biological ones like here). But we learn that biologocal neurons learn by repetition and correlation. When a neuron sees a pattern it tries to repeat it. They probably ran the simulator under different conditions. While giving input to the neurons they forced the output signals. (with simple voltages) The neurons learned these output signals. Afterwards, they just had to give the inputs signals and the neural net would automatically give the output signals it got used to.

    basically the net learns an unlinear function or the inputs. outputi = fi(input1,input2,input3,input4 ...) and these are all voltage pulses (caused by chemical reactions and input signal from the computer)in the neural net.

  15. Re:Just because we can? by Idarubicin · · Score: 2, Informative
    I know that these experiments are fundamentally wrong , no matter what justification you choose to attach to them. They go way beyond normal experimentation, because they directly affect consciousness,

    Well, no--they don't, unless you use a really loose definition of consciousness.

    The construction being used in the Florida study wasn't a brain. It was twenty-five thousand cultured neurons in a dish. (For comparison, a human brain contains roughly a hundred billion neurons; a rat brain one or two hundred million. A fruit fly has about a hundred thousand neurons: four times as many as were used in this experiment.) On this scale, neuronal cells don't exhibit consciousness--are fruit flies conscious? They're just another cell type that happens to have certain properties. Some of those properties--their ability to transmit and regulate small electric currents, and their ability to form interconnects in response to various stimuli--make them appropriate for an adaptive system, but they are not thinking or conscious.

    If a scientist takes cells from a particular organ of the body and grows them in a petri dish, they will often exhibit some of the properties that they showed in the bulk organ. Neuronal cells can conduct electrical impulses, for example. Cardiomyocytes (heart muscle cells) can form sheets and twitch in synchrony. Osteoblasts (bone cells) will start to mineralize. That doesn't mean that neuronal, cardiomyocyte, or osteoblast cultures are little tiny brains, hearts, or bones. It certainly would be absurd to treat them as such from a legal, moral, ethical, or scientific standpoint.

    --
    ~Idarubicin
  16. Re:One question... by Quantum+Jim · · Score: 5, Informative

    why didn't they try to crash the plane? What sort of positive/negative feedback did they use?

    The second article stated that neurons were given information on the tilt of the airplane:

    To control the simulated aircraft, the neurons first receive information from the computer about flight conditions: whether the plane is flying straight and level or is tilted to the left or to the right. The neurons then analyze the data and respond by sending signals to the plane's controls. Those signals alter the flight path and new information is sent to the neurons, creating a feedback system.

    It seems that this experiment builds on earier research by DeMarse, Wagenaar, Blau, and Potter in 2001 called the the animat. It wondered in a box without goal-specific behavior. However, it also tended to specific patterns and states. That is a very readable article - I highly suggest you read it.

    But why did the neurons want to stablize the aircraft? I couldn't find a paper on the aircraft experiment, but a second paper, "Removing some 'A' from AI: Embodied Cultured Networks" (by Bakkum, Shkolnik, Ben-Ary, Gamblen, DeMarse, and Potter, 2004) summarized another experiment where neurons were trained to keep a set distance from an object. The paper is the first article on the same page of publications as the first paper. It seems that the neural network responded nonlinearly - that is, it changed state from one behavior to another one - when the input stimulus frequency was adjusted (correct me if I'm wrong). So by changing the input stimulus frequency, they were able to train the network. I gather that the new experiment simply uses when certain "level = good, nonlevel = bad" stimuli. It's a long way off from Robocop II, but it is a start.

    --
    It is impossible to enjoy idling thoroughly unless one has plenty of work to do.
    - Jerome Klapka Jerome
  17. Re:Abby someone by pipingguy · · Score: 4, Informative


    What hump?

    The quoted dialogue above is a hilarious exchange from an extremely funny movie. They made it in B&W and it still worked in 1974. Today it's quite a cult classic.

    I haven't seen a slashdot name of Abby Normal yet and you can always slip brains through slot in door after 5PM.

  18. From other sources by Rui+del-Negro · · Score: 2, Informative

    From other sources I've read (magazine articles, SF stories, etc.), I think the neurons will generally try to "stabilise" the input signal. So I suspect a plane flying straight produces no input, or a flat wave, while a change of direction introduces a change in the signal (ex., voltage or frequency increases as the angle gets steeper).

    The network eventually "learns" what signal it should output to stabilise its input and either forms separate groups to handle each direction (up, down, left, right), or just one complex network, where changing one input can actually have some impact on unrelated outputs, but things eventually balance themselves by feedback (cybernetics).

    Or maybe they just connected a keyboard to some of the neurons and typed "y0u r t3h n00bz0r", whenever it strayed off course. ;)

  19. Re:working backwards by TheAntiCrust · · Score: 2, Informative

    No, the chicken cae first according to evolution, if the naming convention of eggs is that the egg is named for the animal it came from and not what it houses. Lets call the animal that came before the chicken, Animal X, then it is an Animal X Egg that a chicken hatched out of.

  20. Re:teh living computer by ralmin · · Score: 2, Informative

    This time the story comes around again, and it has been embellished even more! It was debunked on Snopes here, back in 1999!

  21. Re:One question... by NeuroHx0r · · Score: 5, Informative

    We did not report LTP because it is NOT LTP. In fact, we are using and effect reported by Eytan, D., Brenner, N., and Marom, S., Selective Adaptation in Networks of Cortical Neurons. Journal of Neuroscience, 2003. 23(28): p. 9349-9356 in which "high" frequency stimulations (once every second) was reported to depress the response of the network while "low" frequency stimulations resulted in an enhanced response. For our system we tied the network's response to the control surfaces, dedicating stimulations on one channel for pitch, and a second for roll control. Each channel is stimulated separately, and the response (PSTH) is recorded. Control movements are proportional to the current error from straight and level by mapping the error (0 to 180 degrees) to the interval 0 to 100 ms of the PSTH and integrating the difference in response before training, to the current or enhanced or depressed levels. The more error, the more the control surface is moved. The networks only gradually control the aircraft since the Marom effect requires over 15 minutes to develop. The two frequencies are then used to adjust these weights (i.e. number of spikes in the PSTH) to produce optimal flight. The neurons/network don't seek optimal flight in the classic sense. Instead, we adjust the weights (using high and low Freq. stims) in the network to produce that result. It is a very simple system and our only interest in it is in terms of those changes within the network and the possibility to extend it to more of the network than just two or three different channels. Hope that helps.. Tom DeMarse

  22. Re:Human neurons... by Hognoxious · · Score: 2, Informative
    Patients are overcome with the desire to wallow in their own feces.
    They must have been doing that already, because pigs roll in mud. And they always shit as far from the food as possible.
    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."