Hi -
We've done a simple regression 2nd level analysis: 11 subjects con* images
entered and a behavioral covariate entered into simple regression basic
model. The SPM map is compelling, but we'd like to see a bivariate
scatterplot of individual activation against the behavioral variable. My
question is: how to get the individual activation values for such a plot?
We tried getting t-scores from individual contrasts for voxels that survive
a SVC - with the SVC volume being exactly the cluster of voxels that
correlated with the behavioral measure in the group-wise basic model above.
The resulting values (t-scores) do not appear to correlate with the
behavioral variable. We tried this same SVC procedure with a couple other
ROIs that overlap with the voxels that correlated with the behavioral
variable in the group-wise basic model: again, the t-values don't seem to
relate strongly with the behavioral measure.
Is there another route to getting numbers that represent individual
'activation' in a given region for a given contrast that can be plotted
against a behavioral variable of interest - and know that these values
underlie the group-wise, simple regression finding?
Thanks,
Emiliana Simon-Thomas
UC Berkeley
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