Dear FSL list
In featquery, I would like to use the average peristimulus time course of the mask
(ps_tsplotc_zstat1.txt ), and convert the reduced raw data to % BOLD change. What is the
respective baseline ?
Various posting on fsl list suggest to use either a baseline of 10000, as the first level data is
grand mean scaled to that, or better, to use the filtered_func_data.nii.gz. Does this mean the
baseline is obtained by
(1) using the mask in lowres space to obtain the mean timecourse of the filt_func_data.nii.gz
using fslmeants? However the output is not the same as the mean_mask_ts.txt in the featquery
directory.
Or, do I use the mean_func.nii.gz in the .feat directory, and just extract the baseline value using
fslstats -M without any mask ?
(2) then, the % BOLD change is calculated by
(ps_tsplotc_zstat1.txt*height of regressor)/ baselineofROI
(3) finally, with the correct conversion the min, max and mean % BOLD change of the peristimulus
timecourses should be close to those reported as PE-values in the featquery stats table. Is that
correct ?
Many thanks for your information!
Betina
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