Higher level models for fstats (general stats question, FSL)

I feel very sheepish asking this question, but I’ve never had to do this before and I’m not sure how to do it “right”, and google is being unusually cagey,

I have two groups of subjects with multiple runs of a task that contains 4 conditions. For each run, I model each condition as a t-contrast. For each run, I also run an omnibus f-test across the 4 conditions.

For the t-contrasts, at the subject level, I typically run a fixed-effects (-fe) analysis in FLAME across the copes from each to get a single subject cope/varcope per contrast that I can pass to a mixed-effects (-flame1) group analysis. Simple enough, for t-contrasts.

For f-contrasts, I have a map of fstats that tell me where the model explained a lot of variance in each voxel. I don’t know if it makes any sense to run a fixed effects analysis over f-stat maps to get an across-run value. (The f-distribution is certainly not normal!) And can I then take the results of those combined single-subject fstat maps up to a higher level to do a between group analysis? Do I act as if they’re just standard tcontrasts in FLAME, or do something else?

Someone must have solved this, and I’m not sure why it’s so tricky for me to figure out how. :slight_smile:

Thanks!
Todd

Hi ! I’m actually stuck on this same exact problem, did you figure it out ?
Thanks lots,
Raphaëlle