Dear Fahimeh,
The time window should indeed be the part of the ERP that you want to
include in your DCM. That would usually include a stimulus and the
time following the stimulus so a window [-200 0] if 0 is the time of
the stimulus is not what one would usually do. If you don't include
some part of the ERP in the model it will not appear in the results
and will be ignored by DCM altogether. Peri-stimulus time is just time
defined in relation to the stimulus. It's not the time of the stimulus
or before the stimulus if that's what confused you.
Best,
Vladimir
On 29 Apr 2011, at 13:33, Fahimeh Mamashli wrote:
>
> Dear Vladimir,
> Thanks for your attention.
> I have a question about time window defining in DCM data and design
> part:
> in manual it says that we should define the 'peri-stimulus time that
> we want to model' like -200 to 0. when I run the DCM program, in the
> result I can only see the ERP time courses in 'ERP mode' for only
> this time window -200 to 0.
> should I change the peri-stimulus time window? did they mean which
> time window we want to model or exactly peri-stimulus time?
> if it is for peri-stimulus time, how I can see the full ERP time
> courses in 'ERP mode' in the result?
>
> Thanks a lot in advance for your kind help.
>
> Best wishes,
> Fahimeh
>
> ------------------------
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> Max Planck Institute for Human Cognitive and Brain Sciences
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>
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