[Freesurfer] Where are time series from adjusted (post selxavg3) ROIs

Dear Freesurfer experts

I have been going through the documentation trying to figure out how to extract the time series for an ROI (Posteriorcingulate) after removing the regressors that I put in my mkanalysis-sess. I have run the selxavg3. 1. Is this time course what is in the meanfunc.nii.gz? 2. If it is, how do I pull this out in matrix format (.mat) out of the where I basically get one mean adjusted value for the ROI at each timepoint? (e.g. For the Posteriorcingulate, I want 210 values representing the mean activation after removing the effect of my covariates wm and css for each of the 210 timepoints). 3. Is this information in the X.mat file? If so, what is its location?

Thanks Erik Jahner