Dear David:
A similar design was outlined and analyzed using auditory data in Friston et
al's paper on DCM (Friston KJ, Harrison L, Penny W. Dynamic causal modeling.
NeuroImage 2003; 19: 1273-1302). See sections 3.1.1 and 4.2. I think this
model can be applied to your data as well. Remember though the initial SPM
design must include conditions/covariates that model finger tapping and time
dependent effects in order for those vectors to be available to your DCM
design.
Regards,
Darren
-----Original Message-----
From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]] On
Behalf Of David Kideckel
Sent: Wednesday, December 20, 2006 7:54 AM
To: [log in to unmask]
Subject: [SPM] DCM Design
Dear SPMers,
I posted this question over a week ago and have not heard a response yet.
Can someone with knowledge in this area please respond.:)
I am trying to create a meaningful DCM design, and want to know if the
following experiment can be modelled as such:
Finger tapping: 2 runs total
Blocks of 20 s of finger-tapping, followed by a 20 second block of rest, for
a total of 6 minutes (each run).
This design has been utilized in Structural Equation Modelling, and so it
seems to fit within DCM too. Is this correct?
For this design, I was thinking that the direct input would be the
finger-tapping, and the contextual input would be the within-block time.
I look forward to hearing from someone.
David Kideckel
PhD Student, University of Toronto
Toronto, ON, Canada
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