Dear DCM users,
I'm trying to estimate DCMs on fMRI data with DCM10, and the EM always
converges in 4 steps, resulting in parameters very close to zero in B
and C matrices with low p-values and uniform values in A.
My models are defined with three areas fully (reciprocally connected)
intrinsically, a single input, connected to each area, and what is
varied in the model space is the effect of the input on intrinsic
parameters (B), but always in such a way that the two edges of a
reciprocal connection are both either affected or unaffected by the
input.
I suspect that my uninteresting results are a consequence of the
highly symmetric model definitions. Can that be the case?
I'm also not using any confounds (X0). Can that cause a problem?
Thank you for any help,
Mihály
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