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Hi Daron, The problem is that your block size is longer than the cut-off frequency for your high-pass filter (128 s). This would be a problem in both SPM2 and SPM8, so you must have done something different in the SPM2 analysis. As an aside - the high-pass filter is included to remove low frequency drifts in signal due to scanner instabilities, so long block sizes are generally not recommended in fMRI studies as a rule. Hope this helps, Rich. 2009/11/5 Daron Owen <[log in to unmask]> > Hello, > > I'm moving from SPM2 to SPM8, and trying to reproduce results to make sure > everything is working properly. > > The data set I'm testing is analysed with a simple block design, and I'm > seeing no activation with SPM8 where I was seeing plenty with SPM2. > > The only thing that seems to be different is what is happening to the > design matrix after model estimation (Classical) in SPM8. The attached > images show the design matrix before and after model estimation. I have the > same problem in both Windows and Linux versions of SPM8. > > If anyone has an idea what might be causing this and how to correct it, > your help would be greatly appreciated. > > Thanks, > > Daron > > -- > > > ------------------------------------------------ > Daron Owen > Ph.D. Candidate > Medical Biophysics > The University of Western Ontario > > E5-107 Lawson Health Research Institute > St. Joseph's Health Care (London) > 268 Grosvenor St. > London, Ontario, CANADA N6A 4V2 > tel: (519) 646-6100 x65732 > ------------------------------------------------ > > -- Richard Masterton, PhD Postdoctoral Fellow Brain Research Institute