I am running mri_glmfit using the --pvr option and do not get a pcc.mgh file with the output. I found an old thread from 2017 in which Douglas Greve explained that
"mri_glmfit will not generate a pcc file with --pvr. I think I just did not get around to adding support for this."
Have there been any updates to fix this? Is there a workaround to get pcc files using --pvr?