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sinjan.j
Jul27-11, 12:01 PM
I know the fact that, if the total strength of the nerve signal exceeds the threshold at axon hillock, it triggers an action potential. But if someone asks me a question about axon being the nerve impulse generator or the structure responsible for transfer of information, then I would say that both are correct. But, if you have to chose any one of the two, what will you chose and why?

Ryan_m_b
Jul27-11, 12:30 PM
If by nerve post you mean "action potential" I wouldn't call the axon the generator. The main body of the neuron starts the action potential which travels down the axon. I'm not sure what you mean by transfer of information?

Pythagorean
Jul27-11, 05:22 PM
transferring information refers to transfer of a signal or energy, without necessarily transferring matter. I.e. it generally refers to the energy disturbance propagating through the matter (like a wave). But it also must be coherent, and retain shape above noise levels so that it can be consistently relied on (i.e. you're respiratory system needs to know the C02 levels consistently against a changing baseline, it can't be confused by noise).

OP:
the currents coming into the axon hillock aren't really impulse shaped from a information processing point of view. The population of voltage-sensitive channels along the membrane generate the impulse, initially in response to the current at the hillock, but like a chain reaction, each sub-population of channels after that is triggered by the population before it, so I don't know how you could choose one or the other, unless you loosened up your definition of impulse. Axons definitely transfer information. Before scientists knew about the cascading current channels, they were surprised at how great of conductors neurons were.

sinjan.j
Jul27-11, 11:10 PM
Thank You very much.

That Neuron
Jul28-11, 08:28 PM
Really everything can be called information... Sure from a human perspective some processes 'seem' to transfer info, while others 'seem' purely random, but even random systems transfer info. Really info (in terms of the brain or algorithms on a computer) is not a physical concept, info, as in momentum position, mass etc are, but action potentials transfer roughly no more info than any other system of the same temperature and mass. Our brains are adaptable physical systems that control our behavior, a lot of the time people refer to our eyes as processing info and then sending it to our brain, but really when simplified, its simply physical.

The brain is just a scaled up convoluted version of a marble run (http://www.youtube.com/watch?v=eEXm4OjOVWY&feature=related)

Would you say the marble transfers info?
the same applies to the brain.