Dear FSL experts,
A colleague once told me that it is valid to create contrasts in FEAT that include both the original main EV(s) and the respective temporal derivative(s) by giving both weight 1 (after setting the option "Real EVs" in FEAT; I use an event-related fMRI design with Double-Gamma HRFs along with their TDs). I was told that this contrast might better account for activity due to shifts in the BOLD signal. However, I do not find a lot of papers that report using this method. Can someone advise me on whether this indeed is a valid method to use. What is the exact difference compared to the standard approach that only includes the original EVs in the contrasts?
Thanks a lot for your help and advice.
Best regards,
Henk van Steenbergen
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