Hi Simon
> Hello,
> I am struggling to figure out what parameters have to be assigned to
> the microtime resolution and microtime onset sections for the first level.
> I have performed slice timing correction on my data and I have 69
> slices so my guess is that my microtime resolution should be 69 (1 bin
> = 1 slice).
>
microtime is the binning of the hrf model, you can use any value really
but the number of slices or a multiple of that is a logical choice, with
the microtime onset aligned with the reference slice in your slice timing
> These slices have been acquired with a multi band factor of 3. I used
> fmriprep for the preprocessing and the pipeline indicates that the
> bold runs were slice time corrected to 0.851s.
> By looking into the dicom headers file, it seems the slices 23, 46 and
> 69 were acquired at 0.85s (not sure why there is 1ms difference).
now because you have SMS, you have 69/3 = 23 time bins, and 'you'
selected slices 23, 46, 69 as references (you only can decide if
choosing slices acquired at 850ms makes sense, it does look like the
middle of a 1.7sec TR which is likely given your SMS factor) -- for
mircrotime this means that a logical choice is to make 23 bins and onset
at 12
cyril
--
Dr Cyril Pernet, PhD, OHBM fellow, SSI fellow
Neurobiology Research Unit,
Building 8057, Blegdamsvej 9
Copenhagen University Hospital, Rigshospitalet
DK-2100 Copenhagen, Denmark
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https://cpernet.github.io/
https://orcid.org/0000-0003-4010-4632
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