Hi,
I need some help finding out the type of connection (i.e. excitation / inhibition) of a group-level spDCM after running PEB.
I want to compare two groups (A vs. B), so I run a PEB with assigning 1's to A condition and -1's to B condition. The intercept is modelled as well.
Now in order to understand if a connection is inhibitory or excitatory, I ran an intercept model for condition A and condition B separately. Then I inspected the PEB.Ep vectors. However, PEB.Ep shows me some self-connections as positive (but by default they should be negative/inhibitory). So I assume the PEB.Ep does not give me the answer that I'm looking for.
How can I find out whether a baseline connection is inhibitory / excitatory? I need this information in order to interpret the group-level PEB (e.g. being able to say, there was an increased excitation from region A to region B).
Thanks very much in advance
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