SPM’95 Processing Steps - Overview 2) Removal of
gCBF confound (ANCOVA)
SPM’95 Processing Steps - Overview 2) Removal of
gCBF confound (ANCOVA)
- Scans are corrected for slight differences in global
blood flow between scans (Dg) by adjusting the
“average” gCBF (determined by ANCOVA, assuming
a linear model) of each scan to 50.
- Once corrected, differences in scans should reflect only
differences in regional blood flow (rCBF).
- The gCBF correction is actually implemented as a confound
in the design matrix (more on this later).