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Can anybody point me to the papers where scientists have actually "reverse engineered (...) regions of the brain" or present "highly detailed mathematical model

Can anybody point me to the papers where scientists have actually "reverse engineered (...) regions of the brain" or present "highly detailed mathematical models of (...) neurons"? As far as I know, research in those directions is nowhere near as sophisticated as Kurzweil tries to make us believe. The mathematical models for neurons I've seen may reproduce some firing statistics, but they are not at all suitable for actually modelling behavior of a system in response to a stimulus.

T-A 12y ago
http://www.neuron.yale.edu/neuron/ http://www.neuron.yale.edu/neuron/ http://www.artificialbrains.com/openworm http://www.artificialbrains.com/openworm http://en.wikipedia.org/wiki/Brain_implant http://en.wikipedia.org/wiki/Brain_implant
- jakobegger 12y ago
  I'm not sure what you are trying to say with those links. I know that people are working on mathematical models of neurons, it's just that the current models have little in common with real neuronal systems. The only systems that are described nicely are simple systems with very few neurons (eg. reflexes that involve two or three neurons). And more ambitious projects, like the Openworm project you linked to, can't seem to get past preliminary phases...
  - T-A 12y ago
    I'm not sure how you can claim "reflexes that involve two or three neurons" are state of the art or that OpenWorm "can't seem to get past preliminary phases". Neither http://www.openworm.org/science.html http://www.openworm.org/science.html nor http://www.i-programmer.info/news/105-artificial-intelligence/7985-a-worms-mind-in-a-lego-body.html http://www.i-programmer.info/news/105-artificial-intelligenc... look like a preliminary phase to me. That's a system of more than 300 neurons, fully mapped, simulated and working, both virtually and hooked up to real sensors and actuators.
    - jakobegger 12y ago
      I guess what I'm looking for is the comparison of the model with experiment. How do the researchers know that they are simulating c. Elegans, and not just an artificial organism inspired by c elegans?
im2w1l 12y ago
While simulating a human brains should be sufficient to pass the Turing test, that doesn't mean it is necessary.
- jakobegger 12y ago
  I completely agree with you. However, Kurzweil's argument focuses on the fact that he believes we will someday be able to simulate the human brain, and that's something I disagree with strongly.
  - johansch 12y ago
    Saying that we will never be able to simulate a piece of hardware/wetware is a pretty strong statement. (Unless you think there is some kind of magic inside it.)
    - jakobegger 12y ago
      the obstacle is that systems composed of many simple elements quickly become so complicated that we can't simulate them anymore, even if we would completely understand the individual elements.
      - sumitviii 12y ago
        But we have working examples of that machine. The problem is in completely understanding it. If we completely understand it, then it shouldn't be hard to simulate.
        jakobegger 12y ago
        i'd argue against that. Somewhere else in this thread someone brought up weather predictions; even though we completely understand the physics of weather, we can't simulate worldwide climate precisely for various reasons (not enough information, not enough computational resources, chaotic behavior). I think it's the same thing with our brain.

T-A 12y ago

http://www.neuron.yale.edu/neuron/ http://www.neuron.yale.edu/neuron/ http://www.artificialbrains.com/openworm http://www.artificialbrains.com/openworm http://en.wikipedia.org/wiki/Brain_implant http://en.wikipedia.org/wiki/Brain_implant

jakobegger 12y ago
I'm not sure what you are trying to say with those links. I know that people are working on mathematical models of neurons, it's just that the current models have little in common with real neuronal systems. The only systems that are described nicely are simple systems with very few neurons (eg. reflexes that involve two or three neurons). And more ambitious projects, like the Openworm project you linked to, can't seem to get past preliminary phases...
- T-A 12y ago
  I'm not sure how you can claim "reflexes that involve two or three neurons" are state of the art or that OpenWorm "can't seem to get past preliminary phases". Neither http://www.openworm.org/science.html http://www.openworm.org/science.html nor http://www.i-programmer.info/news/105-artificial-intelligence/7985-a-worms-mind-in-a-lego-body.html http://www.i-programmer.info/news/105-artificial-intelligenc... look like a preliminary phase to me. That's a system of more than 300 neurons, fully mapped, simulated and working, both virtually and hooked up to real sensors and actuators.
  - jakobegger 12y ago
    I guess what I'm looking for is the comparison of the model with experiment. How do the researchers know that they are simulating c. Elegans, and not just an artificial organism inspired by c elegans?

im2w1l 12y ago

While simulating a human brains should be sufficient to pass the Turing test, that doesn't mean it is necessary.

jakobegger 12y ago
I completely agree with you. However, Kurzweil's argument focuses on the fact that he believes we will someday be able to simulate the human brain, and that's something I disagree with strongly.
- johansch 12y ago
  Saying that we will never be able to simulate a piece of hardware/wetware is a pretty strong statement. (Unless you think there is some kind of magic inside it.)
  - jakobegger 12y ago
    the obstacle is that systems composed of many simple elements quickly become so complicated that we can't simulate them anymore, even if we would completely understand the individual elements.
    - sumitviii 12y ago
      But we have working examples of that machine. The problem is in completely understanding it. If we completely understand it, then it shouldn't be hard to simulate.
      - jakobegger 12y ago
        i'd argue against that. Somewhere else in this thread someone brought up weather predictions; even though we completely understand the physics of weather, we can't simulate worldwide climate precisely for various reasons (not enough information, not enough computational resources, chaotic behavior). I think it's the same thing with our brain.