External Email - Use Caution
I’ve been using mri_glmfit to regress out motion correction parameters and linear trends and saving residuals in surface space by first generating a QA matrix for the volume:
mri_glmfit --y ${source_dir}/${r}/${filepat}.${surf}.${hemi}.nii.gz \ --glmdir ${source_dir}/${r}/{hemi}.detrend \ --qa \ --surf ${SURFTOUSE} lh Then merging the QA and MC matrices into a single matrix of nuisance regressors:
paste ${source_dir}/${r}/lh.detrend/Xg.dat mcprextreg > nuisance
And finally, regressing out the nuisance values and saving the residuals mri_glmfit --y ${source_dir}/${r}/${filepat}.${surf}.${hemi}.nii.gz \ --glmdir ${source_dir}/${r}/${hemi}.detrend \ --X nuisance \ --no-contrasts-ok --save-yhat --eres-save \ --surf ${SURFTOUSE} ${hemi}
Is there a straightforward way of obtaining mean white matter and csf signal in my nuisance regressor matrix? I was unable to find any preprocessing step or application of mri_glmfit that will provide these values or regress out these values automatically.
(Also note: the —qa flag is not documented in the mri_glmfit help; I must’ve learned of it from a previous email to this list)
Thanks
/********************************************** * Chris McNorgan * Assistant Professor * Department of Psychology * University at Buffalo, * The State University of New York * http://ccnlab.buffalo.edu/ * Office: 716.645.0236 * Lab: 716.645.0222 **********************************************/