Background: I am using fMRI individual level analysis data from my supervisor's previous paper. Before I can perform PPI on the data, I need to update the 1st level analysis batch files since they currently refer to non-existent directories and cannot be run correctly.

Problem: I updated the 1st level analysis and estimated the model successfully, but now the contrasts previously used in the study are gone and I need to set them up again for the new SPM.mat file. I have a .txt file with all the contrast names and weights, but when I try to set it up for the new SPM.mat using the batch contrast manager, I get an error claiming my contrasts vector is too long. See below: enter image description here

Troubleshooting so far: I checked and I can easily apply my contrast vectors to old SPM.mat, but not to the new SPM.mat. This suggests that I must have messed something up when performing the 1st level analysis. However, I kept everything (including conditions) exactly the same and only changed the filepaths. I do not know how it is possible that I ended up with a different number of parameters than in the old analysis.

Question: How do I correct my 1st level analysis to obtain the correct number of parameters for the contrast vector that I have? I seem to only have 48 parameters, but my contrast vector assumes I have 156.

Thanks SO MUCH to anybody who spends their time reading the question and trying to help. I am still very much learning SPM and keep getting stuck all the time; getting some help with this problem would be amazing



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