Chapter 9.2 Fitting experimental curves with models
Curve Fitting
When the "Run Fitter" option is chosen from the Miscellaneous button,
a somewhat different panel
appears.
Steps in fitting an experimental curve
- Press the "Read Data" button to import the curve (from *.dat file list)
- Choose the "Variable to fit" (from browser similar to that for "Plot What" )
- Choose the "Parameters to vary" (again from browser)
- "Do fit" (runs the simulation repetitively, with the fitter changing the paramater values as it searches for best fit) or
- "Single Run Fit" (for a quick look)
Examples of some fits to the Hodgkin-Huxley equations are shown below.
The data imported was from voltage clamp records was saved as files in Ascii format
which were edited to remove all headers leaving only the number of points (pairs of rows).
Sodium current for brief step to -10mV level
HH "m" state for same voltage clamp step
Potassium current for same conditions
This fit is not very satisfactory nor is a longer pulse where
the steady-state is more prominent.
Surprisingly, a better on can be done with a lower power (3rd in place of the HH 4th, used in generating the curve.
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