Hi there,
Please could I have some help with warping a probabilistic ROI mask (.nii)? I am working with secondary data. The ROI mask is from a localiser task in a previously published study and does not match a specific MNI template. The authors have suggested I should be able to re-slice the masks to get them in the same space as my desired template image.
The data that I am analysing is also secondary from an open-access data set. These data have already been pre-processed including normalisation, so each participant's functional and anatomical files have already been warped to an MNI template (MNI1522009templateSSW.nii).
I have been trying various co-registration and normalisation processes to get the ROI mask into the same space as the participant data. Each time they produce an output but it is not correct as my analysis scripts then reject the mask for being in a different space to the data. I'm also not sure whether I should be warping the ROI masks to each participant's anatomical scans (that have already been normalised to the MNI template), or to each participant's functional scans (which have also already been normalised to the MNI template) or whether I should only warp the ROI masks once to the MNI template itself.
I've found that advice online is for co-registration/normalisation is for aligning/warping functional data rather than a mask, and advice for warping ROIs requires SPM output files from pre-processing. The data that I have access to are already preprocessed so I don't have these files.
I have the following .nii files:
The ROI masks
Each participants' pre-processed functional scans normalised to the MNI template
Each participants' pre-processed anatomical files: t1w_mask_anat.nii, t1w_mask_epi_anat.nii, t1w_mni_alignment.nii
Thank you so much for any help, it is much appreciated!
All the best,
Clare
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