Dear all
I have a multiband (8x) epi recording with TR=720ms and 72 slices
I have doubts on setting the proper values in fmri data processing when I use the info contained in the json created by dcm2nii.
the slice timing section reports the following:
[0.31, 0, 0.3875, 0.0775, 0.465, 0.155, 0.5425, 0.2325, 0.6225, 0.31, 0, 0.3875, 0.0775, 0.465, 0.155, 0.5425, 0.2325, 0.6225, ........7 times more........... ]
9 timepoints where I record 8 slices (72 slices for each tr).
I assume it records slices in the following order
0 -> 2-11-20-29-38-47-56-65
0.0775 -> 4-13-22-31-40-49-58-67
0.155 -> 6-15-24-33-42-51-60-69
........
.......
my question is how to fill the proper values of:
"Slice order" and "Reference Slice" in slice_timing
"Microtime resolution" and "Microtime onset" in fMRI model specification
- Slice_order: i put the list of ms of SliceTiming section of the json
- Reference Slice: I can freely select it. usually the middle (in temporal domain) volume(s) is preferable. if I want its equivalent, I here select the fifth (of nine) set of slices. ---> 0.31 ms. ok?
- Microtime resolution: having done slice timing, the manual suggest to match the number of slices specified in slice timing. it is 72 (the total number) or 9 (the set of multiple slices) ?
- microtime onset: the manual tell to match previous slice_timing reference slice, but in its example never talk about ms (as it does for slice_timing). should I put the same value fo slice_timing's ref slice ---> 0.31 ? or middle slice(s), which I don't know. 36?
thanks in advance
regards
Alberto
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