Dear FSL experts,
I would be very grateful for some advice on a problem that I have with higher level FEAT analyses.
I am attempted to run a higher-level FEAT analysis (two sample un-paired t-test) that combines subjects who have one run of a task with those subjects who have two runs.
I.e. for some subjects I have run a standard first-level analysis and for others I have run a fixed effects analysis to combine two runs (just to increase SNR).
I understand that combining unequal numbers of runs across subjects is still feasible according to this thread, if ones uses FLAME1:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind0912&L=FSL&P=R6641&1=FSL&9=A&J=on&d=No+Match%3BMatch%3BMatches&z=4
My question is, if I want to combine single run/fixed effects is the input the following? For example:
subj1.feat/stats/reg_standard/cope6.nii.gz (first level for ONE RUN)
FFX/subj2.gfeat/cope6.feat/stats/cope1.nii.gz (fixed effects - TWO RUNS COMBINED)
FFX/subj3.gfeat/cope6.feat/stats/cope1.nii.gz
etc
These cope images have the same dimensions and appear to be in standard space - however I get an error when trying to run this model: "Registration has not been run for all of the FEAT directories that you have selected for group analysis, Please turn on and setup registration".
This is confusing, as I have run the registration for all my inputs. Also if I run this analysis using the following inputs it works (notice first subject's cope1 image is now taken from a different stats folder NOT the one in reg_standard):
subj1.feat/stats/cope6.nii.gz (first level for ONE RUN)
FFX/subj2.gfeat/cope6.feat/stats/cope1.nii.gz (fixed effects - TWO RUNS COMBINED)
FFX/subj3.gfeat/cope6.feat/stats/cope1.nii.gz
etc
Any advice on what inputs are usually used would be extremely helpful.
Kind regards,
Sara
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