Hi there,
I do a seed region resting state analysis in several steps. In the first I apply all the pre-stats (smoothing, highpass etc), in the 2nd I remove confounds (WM signal etc with an empty EV). In the 3rd I feed in the seeds time series with the residual of the previous step. I see some people do the prewhitening at the confounds step (2nd), others do it when they include the seed voxels time series (3rd). I am not sure at which stage to do it (or maybe in both?). On the website it says it do be needed to make the statistics valid, so I would assume already at the 2nd when confounds are regressed out. Could someone advise me on that?
Thank you very much in advance,
Torsten
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