Hi,
I recently completed a higher-level analysis (using mixed effects: FLAME 1+2) for the group mean of ~150 lower-level copes. The higher-level group map is empty, which seems puzzling. We have seen strong activation for this particular task contrast in other studies, and all of the individual subjects' lower-level copes have activation. I have double-checked the model, EVs, etc.
When comparing this analysis to others, the only difference I can find relates to a warning in the log. The warning (present in all of the higher-level analyses) states: "WARNING: The passed in varcope file, tmpvarcope0014, contains voxels inside the mask with zero (or negative) values. These voxels will be excluded from the analysis." In my other analyses, there are then numbers listed, but in the analysis with blank maps, no numbers are listed and nmaskvoxels=0. I am unfamiliar with this warning and wonder if it might be related.
Would anyone have thoughts on why the maps might be blank or this warning?
Thanks,
Dylan
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