Changing Conductance Values in ChannelBuilder Has No Effect

tsa · Post by **tsa** » Thu Apr 05, 2007 9:45 am

Hello,

I'm having trouble with Channel Builder, I have created a single cell model with 5 currents which cause bursting without stimulus. If I vary the gating variable parameters or the specific potentialsof currents I see effects on cell voltage in graphical output. However if I change the conductance values for a current, even to zero so the current should have no role in the voltage, I see no effect. I can even change the conductance of every current to zero and still see bursting in model. This occurs even if I save the session, close neuron, and reopen it to allow for the model to reset. I'm very perplexed and any help would be very much appreciated,

Tim

Post by **ted** » Thu Apr 05, 2007 11:47 am

Is the Continuous Create button "on" (shows a red "check" mark)?

tsa · Post by **tsa** » Thu Apr 05, 2007 12:29 pm

I'm not using cell builder, where I believe the continous create button is. I've been simply specifying cell parameters in hoc code. If I change parameters in the console I see an effect so perhaps that is the problem. Is there a way to turn continous create within hoc code? Thanks.

Post by **ted** » Thu Apr 05, 2007 3:49 pm

The GUI is far superior to hoc when it comes to interactive exploration of model behavior,
so I automatically assumed that you were using the CellBuilder to specify model properties.

The Channel Builder provides no way to specify channel density. You must assign channel
density via hoc statements.

There is no need for a "continuous create" feature when using hoc to specify model properties,
since all statements take effect immediately when executed. However, to err is human, so
it is always a good idea to verify that what happened is what you wanted to happen. If your
model has only a few sections, you may want to try forall psection() (or just
name_of_section psection()
if there is just one section) to report the properties of all sections.