You can give mkanalysis-sess the slice order with -stc as you would with an ordinary non-accellerated scan. Then give it the number of slice groups with -ngroups nSliceGroups I don't quite remember what nSliceGroups means, but I think it means the number of simultaneously acquired slices.

On 3/28/2022 3:21 AM, Laura Doll wrote:

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Hi everyone,

We are currently piloting an fMRI measurement with multiband sequence on a 3T Siemens scanner to increase resolution, but I don't know how to do the slice timing correction: I assume, that I have to use a slicedelay file instead of the usual up/down/even/odd/siemens flags? But how do I know which slices were excited simultaneously?

Our multiband acceleration factor is 2, if I got our MRI physicist correctly, GRAPPA acceleration is also 2, and we are using a TR of 2s. More details of the sequence are in the attached pdf (which is unfortunately in German).

Looking forward to any suggestions.

Best, Laura

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