Hi,
I would like to run 2nd level analyses, specifically 2 sample t test on 2 different cohorts. These groups were scanned at different times but should have had the same acquisition parameters.
However when i ran the analyse, this error appeared:
** The images do not all have same orientation and/or voxel sizes. **
The function assumes that a voxel in one image corresponds exactly with the same voxel in another. This is not a safe assumption if the orientation information in the headers or .mat files says that the images are oriented differently. Please ensure that you process all data correctly. For example, you may have realigned the images, but not actually resliced them to be in voxel-wise alignment.
Here are the orientation matrices of the image volumes.
For the first group the matrix is : [-3 0 0 81; 0 3 0 -114; 0 0 3 -54]
For the second group the matrix is: [-3 0 0 81; 0 3 0 -115; 0 0 3 -53]
I believe these correspond to the mm transformation matrices (SPM.xVol.M).
The SPM.xVol.DIM are the same for both groups.
I would like to know :
- what do those numbers precisely refer to
- if it is possible to counter this problem and run the analyse.
Thanks in advance for your help,
Dre. Lucile Rapin
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