Dear SPM experts,
I am trying to extract parameter estimates from fMRI data in a set of ROIs using marsbar (version .43). When overlaying these ROIs on 1st level activation maps, there is a large cluster of active voxels within the ROI, so I know there is data to be extracted in all the subjects I am analyzing.
However, when I try to extract the parameter estimates with marsbar (data --> extract ROI data (full options)), no data is parameters are extracted in a large number of subjects; I get the following error:
"Warning: No valid data for roi 1"
I have insured that the ROIs fall completely within the 1st level masks, and that I have the newest version of marsbar. Furthermore, I tried the suggested solution regarding the sampling of NaNs near the edge of the brain, using nearest neighbor resampling, but this also did not help.
I don't understand how there could be no data to extract, as examination of the 1st levels in the contrast I am using shows that there was strong activation that I should be able to find in marsbar. Is there another issue that may be causing this? Thank you in advance!
Best regards,
James
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