Hi,
I am a undergraduate student and quite new to fMRI and SPM . Im trying to analyse some BOLD data and I have a few queries (sorry some maybe trivial) and I was wondering if anyone could help me , I will be very grateful.
1) I have managed to get results for 1st level analysis but I need to find the percentage signal changes in SPM ? Is there a separate button for it ? I want a plot of % change vs time for two different coordinates. I was wondering if I could get this directly ?
2) For my second level analysis, I do not seem to get results if I use the FWE correction in SPM but I do get blobs if I don't use the correction(with threshold 0.001) and they seem meaningful. I have tried doing the preprocessing again but I still cant get blobs when I use the correction. Would it be ok to use the results for uncorrected p values in the group analysis ?
3) How do you find brain regions which correspond to the given coordinates ?
4) Does the HRF vary amongst different subjects ? If so would I need to change the delay or any other parameters when analysing results for different subjects ? Is there anyway for me to know if I need to do this or not ?
Thanks a lot
Ryan
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