Figure 6.
Posterior-cingulate cortex (PCC) and white-matter (WM) seed correlation maps obtained prior to GSR and after the application of GSR, global signal normalization (GSN), and global signal subtraction (GSS). Consistent with the approximation shown in Appendix C, GSN and GSS yield nearly identical maps for all scans. The cosine similarities between the GSR and GSS maps are indicated by the values listed at the bottom along with the corresponding GSR fit coefficients for the seed time courses. As the fit coefficient values approach 1.0, the GSR and GSS maps become more similar.
