Hi,
I have a very basic question on how time constants are modeled for voltage gated channels. I have a tau vs. voltage bell shaped curve from voltage clamp data that I am trying to model using either the direct HH form with double exponentials or the Borg Graham method as in the modelDB examples. I tried running a 5 and 6 parameter fit on MRF using my data but the error was infinite. Also, the Borg Graham form asks for parameters like effective valence and gating asymmetry that I am not sure how to get from the data. Can you please explain how the time constant curves are usually fitted in the models?
Thanks
Time constant modeling

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Re: Time constant modeling
Many steps are involved in setting up and using the MRF, and it is easy to make one or more minor errors that can have disastrous results. You might find it helpful to begin with an example that has a known solution, and use this to verify that the MRF has been properly configured. Always try to write equations and formulas in such a way that optimizable parameters will be positive definite (i.e. always > 0); this will allow the use of logarithmic scaling with helps accelerate convergence to a (possibly local) minimum.yvp wrote:I tried running a 5 and 6 parameter fit on MRF using my data but the error was infinite.
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Also, the Borg Graham form asks for parameters like effective valence and gating asymmetry that I am not sure how to get from the data. Can you please explain how the time constant curves are usually fitted in the models?