Rescaling by the voxel mean will mess up the intensity normalization. Try making your analysis (mkanalysis-sess) with -no-inorm and see if the results are more consistent. They will not be exact because the raw mean time course is not used to create the cespct. Rather it is the regression coefficient of the mean offset regressor. They should be pretty close though.

On 6/7/16 12:22 AM, S.V.Shepherd [work] wrote:

Hi all,

I ran an analysis on data after dividing each voxel mean across the run, and then multiplying by 100. (My intuition was that the percent signal change should be more consistent across varying SNR that the non-normalized betas).

I had naively expected ces.nii and cespct.nii to be equivalent in this case, but in fact, cespct.nii is steeply larger and only imperfectly correlated with ces.nii. What am I missing?

stephen

stephen v. shepherd phd
The Rockefeller University / 1230 York Avenue / New York NY 10065-6307 USA // 212.327.7699
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