Dear all,
I acquired data in interleaved mode from the bottom to the top over the axial section (S >> I) (1,3,5,7...47,2,4,6,8.....46).
I'm doing first-level analyses and found out that I had made the following 'mistake': In specifying the Microtime Onset i thought I had to refer to the slice number of the reference slice i specified for slice-timing, which in my case was 2. With these settings the first-level result of looking at a very simple condition (receiving reward feedback) for a specific subject looked like in Image 1, but many subjects actually showed a similar pattern. This ring-pattern made me worried that I was looking at a motion-artefact. However, after changing the microtime onset to 23 (as i now believe is correct) the result for this specific subject (with all other things being equal, i.e., microtime resoluation being 47) looked like in Image 2. When trying out how much a difference this could actually make I also tried a first-level version with microtime onset being 47 (all else being equal) and the results look like in Image 3. I didn't try how much of an effect these different settings would make at second level, but I was actually quite shocked to see such large differences within one subjects after changing only one parameter. My question is: are these differences expected with these levels of the parameter and if so: what is the best level of the microtime onset?
Thanks a lot in advance!
Best, Jindra
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