Dear Sahil,
I haven't done resting state DCM so far, but I guess that you may just set up
a dummy SPM.mat which may contain dummy conditions. In the specification of
the rsDCM you just have to say "no" when SPM asks you if you want to include
any condition. In this way the field "endogenous" in DCM.options will be set
to 1 as well as the "stochastic"-field. Be sure that you use the recent
version of SPM8 (including updates).
Hope this helps,
Thilo
On Wednesday 14 November 2012 18:05, Sahil Bajaj wrote:
> Dear DCM experts,
>
> I am posting one of my previous posts regarding Resting State DCM once
> again. It would be great if you can guide me sort out this issue.
>
> Currently, I am analyzing resting state fMRI data. I have done the
> preprocessing using SPM8 and 1st level and 2nd level analysis using
> functional connectivity toolbox (
> http://www.nitrc.org/forum/forum.php?forum_id=2295) to find the activations
> and peak co-ordinates of four clusters.
>
> I don't have SPM.mat file of each subject to use in DCM but what I have is
> SPM.mat files of each of the regions, obtained from 2nd level analysis
> (from functional conn toolbox).
>
> So 1). How can I obtain SPM.mat file for each subject to define VOIs of
> each subjects and define models further and
> 2). What contrast/condition & onset/duration should I use in SPM to obtain
> SPM.mat files ? I have a rest period of 400s (200 scans).
>
> I would greatly appreciate any kind of help. It would also be great if you
> could please refer me to someone or some paper where DCM has been used for
> resting state.
>
> Thanks a lot !!
> Regards,
> Sahil
>
> --
--
Thilo Kellermann
RWTH Aachen University
Department of Psychiatry, Psychotherapy and Psychosomatics
JARA Translational Brain Medicine
Pauwelsstr. 30
52074 Aachen
Germany
Tel.: +49 (0)241 / 8089977
Fax.: +49 (0)241 / 8082401
E-Mail: [log in to unmask]
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