I have questions about implementing 3dFDR on a Group statistical map output by the matlab package groupana (and as far as i can tell, does not include FDR curves).

I ran a 4-way ANOVA and am interested running 3dFDR on a 3-way interaction map. There is the coefficient sub-brik and F sub-brik associated with the 3-way interaction. I've tried applying 3dFDR to the entire anova bucket (masked for non-brain areas), but then I do not understand how to view the data properly in the output. I've also applied 3dFDR to only the coefficient sub-brik, and to only the F sub-brik. The F sub-brik then yields no data. Which dataset is best to use with the 3dFDR command?

Also, from my understanding, FDR analysis should be applied to the entire brain, with no initial thresholding procedure. Is this correct?

Thanks for your help,
Helen