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Hi

I have been using channel builder to create a few channels. One of the channels causes oscillations in the resting membrane potential, which only occur when I include that channel in the model. However, I still get the oscillations when the channel conductance is set to zero. Shouldn't this be the same as not including the channel.

Thanks

I was trying to set the maximum conductance to zero through the hoc code, when I went back and changed it using the channel builder and then re-loaded the hoc code, it did give the same result as not including the channel.

The Channel Builder, like the CellBuilder, works by executing a set of hoc statements. Any substantive manipulation of the Channel Builder (such as, but not necessarily limited to, changing the value of a parameter) will cause re-execution of those hoc statements. This may overwrite parameter assignments you have made with your own hoc code.

It is often useful to combine hoc and the GUI builders--for example, use the GUI tools to set up a "standard" or "control" model, then use a "for" loop to run a series of simulations that iterate over a range of parameter values. However, be careful not to "step on" anything you have done with your hoc code. A reasonable work flow is

1. Use the GUI to tweak stuff interactively as much as you like
2. Use hoc statements for automated (noninteractive) tasks

If you ever go back to step 1, realize that it may undo parameter assignments you made in step 2. But since those assignments were made in hoc, it is easy to gather them into a proc that you can call whenever you want to return to that particular set of parameters.