I am using the latest version/update of SPM5 with MatLab 7.0 on Windows XP Professional 2002, service pack 3.
I have 1st-level analyses (.con hdr/image files) consisting of the difference between 2 task conditions for each of 2 groups (patients and controls).
There is a statistically significant difference between the 2 groups in years of education. I would like to include this as a "nuisance" variable at 2nd-level analysis. I would also like to include a "covariate of interest" (in this case fractional anisotrophy- FA). There is no correlation between these 2 variables.
What test should I use at the 2nd-level (and subsequent definition of contrast weights) to answer the queston:
Is FA related to the difference in BOLD response between groups?
Thank-you for your help,
Julie E. McEntee, M.A., C.C.R.P.
Senior Research Program Coordinator
Department of Psychiatry- Neuroimaging
Johns Hopkins University School of Medicine
600 N. Wolfe St./ Phipps 300
Baltimore, MD 21287