Hi,
I‘m following the DualRegression/UserGuide to run dual regression to analyse a set of resting-state studies (already normalized to the EPI template) to assess differences between the sensorymotor network of patients (n=27) and normal subjects(n=18).
MELODIC results look fine and the sensorymotor network can be clearly identified (in this case IC 3).
However, the tmaps obtained during step 2 of dual_regression (I’m using the dual_regression script shipped with FSL 5.0) poorly overlap with the component I selected as SMN (their average shows indeed quite a large overlap with CSF).
On the other hand, if I use FEAT to run the second part of the dual regression (using as EV the timeseries from stage 1 of the dual-regression, i.e. dr_stage1_subject[#SUB].txt), the mean across all the subjects looks like the SMN, as expected.
In doing this I turned off all the options in feat (no FILM prewhitening, no spatial or temporal filtering and so on…).
Am I doing something wrong or actually FEAT is likely to perform better than fsl_glm for this task?
More in general, is there any specific reason why fsl_glm is used in the step 2 of dual_regression instead of using FILM?
Thanks for any help
mario
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