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Hi Maria: I am reading the Fox paper .I can not understand some details in your paper , although I have discuss with my colleague. I hope you can help me. 1) In the section *Preprocessing of Functional Data* of the paper, what does the sentence *'Each fMRI run was intensity scaled (one multiplicative constant over all voxels and frames) to yield a whole brain mode value of 1,000 (not counting the first four frames *)' mean? Can you explain to me how to scale the data in details? 2)In the section *Correlation Techniques *of the paper,* * what does the sentence '(ii) the whole-brain signal averaged over a fixed region in atlas space' mean? what does *the whole-brain signal *mean ? How to select the fixed regions? Whole brain signal does not mean all brain voxel averaged,does it ? Looking forward to your response. Sincerely yours LeiNa On 10/14/05, Maria Densmore <[log in to unmask]> wrote: > > Hello , > > Thanks for your feedback. > I still need clarification of my two concerns. > > 1) I don't quite understand how to set my design matrix since there is no > baseline condition to subtract the task from. What I do have is, one task > (eyes closed)that continues throughout the entire 110 volumes acquired. > > 2) I'm also not sure if this TRUELY translates to a PPI analysis in SPM or > if > it's something I won't be able to replicate using SPM. > > > Comments on the VALIDITY of a resting state analysis are greatly > appreciated. > > Thanks for you time, > Maria > > > > > Dear spm group, > > > > I've been asked to analyze a data set that was scanned with the same > > parameters > > as the paper: Fox et al "The human brain is intrisically organized into > > dynamic, anticorrelated functional networks", PNAS July5,2005 > > > > This data set was not analyzed using SPM but seems to correlate time > > series data > > for the voxels or regions of interest during a resting state. > > >