hello SPM,

Im doing a Resting state fMRI study looking at functional connectivity.

I want to extract regressors using 'MARSBAR Extract ROI data (full options)' to use for my 1:st level analysis (SPM->Stats->fMRI model specification).

My question is what scaling options I should select. It is my understanding that this depends on what you want to do with the data, so for our study we will compare two populations using SPM->Stats->Factorial design specification.

Does this mean that we should use "session specific scaling" and "scale grand mean to" 100 and specify "Global normalization" in my 1:st level analysis? The reason I am asking is that everywhere I look the documentation says that grand mean scaling is only for PET.

/Andreas