> For the purpose of SEM, should I have maybe not apply the “*100”. Could I
> correct this in a post-hoc fashion on the .1D ROI time series data using 1deval or 1dmatcalc?
Post-hoc scaling with 1deval or 1dmatcalc should be fine.
> if it’s head motion or some other abnormality causing the signal to shoot up
> how can I adjust for this without having to re-deconvolve the data and
> regressing it out and then having to redo the 3dsynthesize, etc.
You'd be probably better off by simply censoring out such spikes.
Good luck,
Gang