Hi
I want to calculate delay maps (in sec) for fmri data analyzed using FEAT tool.
My paradigm is : blank[12vol]_A[12vol]_blank[18vol]_A[12vol]_blank[12vol]
(with TR=5)
Run with the following FEAT's parameters:
EV's -
60 60 1
210 60 1
apply temporal filtering-ON
add temporal derivative-ON
First - If stats/pe1 map is the parameter estimate image for EV 1; what in the
meaning of pe2?
How its represent delay value?
Dose temporal derivative calculate for each voxel separately?
Way its have negative values?
Next, for delay maps (in sec, TR=5) I run:
fslmaths pe2 -mul 100 -div pe1 -mas ../cluster_mask_zstat1 delay1
fslmaths delay1 -mul 5 -div 100 delay1sec
Dose delay1sec map represent each voxel delay in sec? (again- why the
negative values?)
Many thanks
Moran
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