Re: [Genesis-sim-users] V-clamp on dendrites?

[Kai Du <kai...@gm...>]

Dear Dave,

Thank you so much for the link! It helps me a lot to understand the "clamp"
in GENESIS.

2015-03-03 17:08 GMT-08:00 Dave Beeman <db...@co...>:

> As Dieter pointed out, it could be that the smaller size of the dendrite
> compartment might require different voltage clamp parameters.
>
> Also look at the "Mini-Tutorial on Voltage Clamp Circuitry Tuning" on the
> GENESIS web site.  Here is a direct link:
>
> http://genesis-sim.org/GENESIS/UGTD2-CNS/Tutorials/
> advanced-tutorials/Mini-tuts/vclamp/index.html
>
> I hope that this is helpful.
>
> Dave Beeman
>
>
> On Mon, 2 Mar 2015, Kai Du wrote:
>
>  Hi All Genesis Users,
>> Do you ever have any experience in applying V-clamp on dendrites?
>>
>> I just tried to apply the V-clamp to dendrites and I found it had to use a
>> time step of 1e-20 second!!! or  simulations were simply crushed!
>>
>> Do you how can we change the parameters in the  "V-clamp" settings so we
>> can
>> use a bigger time-step to clamp dendrites.
>>
>> This is what I use now:
>> ===================================================
>> create RC /clamp/lowpass
>>   setfield ^ R 1 C 1e-5
>>
>>  create diffamp /clamp/vClamp
>>    setfield ^ saturation 999.0 gain 1
>>
>>   create PID /clamp/PID     // Values taken from squid example
>>  setfield ^ gain 1e-5 tau_i 1e-5 tau_d 1e-7 saturation 999.0
>> ============================================================
>>
>>
>> btw, I also tried V-clamp on passive dendrites, it also need a very
>> "small"
>> time-step, say, 1e-14 second. By contrast, the V-clamp works well to the
>> soma -- a time step of 7e-6 second was needed.
>>
>> --
>> Best Regards,
>>
>> Kai Du,
>> PhD student
>> Department of Neuroscience
>> Karolinska Institutet
>> Retzius väg 8
>> S-17177 Stockholm, Sweden
>>
>>


-- 
Best Regards,

Kai Du,
PhD student
Department of Neuroscience
Karolinska Institutet
Retzius väg 8
S-17177 Stockholm, Sweden