Dear spm-list,
I have conducted preliminary whole brain analyses in a pre-test -
post-test design for two groups. The other group shows activation
changes between the sessions in a certain brain region, the other one
doesn't. However, when I conduct an ROI analysis for this region, I find
a very similar activation change between the two groups; that is, it
doesn't seem that the other group shows a change in activation between
the two sessions of a greater magnitude than the other group. What could
be the reason for this? I have run the ROI analysis with both mean and
peak activation, but both look the same.
Thanks for and ideas and help!
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