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Hello everyone, I was hoping for some reassurance that I am on the right track re 1st level analyses. The data I have consists of a total of 24 runs per participant (12 per session). Rather than running the entire first-level analysis using the FEAT GUI for each of these runs, which would have involved registering the structural to standard images 24 times per participant, I attempted to save some time by conducting the structural to standard registration only once per subject per session, using flirt via the command line. I have still used FEAT for motion correction, but made sure I deselected all the options on the registration tab. I would now like to use FEAT for the remainder of the 1st level analysis. I am assuming that the 4D image I should use as input for the stats step is the filtered_func_data.nii image in the main output directory. Is this correct? I would also like to add motion parameters as events of no interest using FEAT. However, the "add motion parameters to the model" button is disabled unless you conduct the prestats and stats in the same FEAT run. From reading this mailing list, it seems that one can add the 3 translation and 3 rotation parameter estimates from the prefiltered_func_data_mcf.par file using the "add additional confound EVs" button. Using the 1-column format, it should be possible to select this file directly, as the format of the prefiltered_func_data_mcf.par is consistent with the format of multiple 1-column EVs in the same file (TRs = rows, and EVs = columns). Is this the case? Finally, although I intended including columns modeling individual spikes in the timeseries (identified from the prefiltered_func_data_mcf_rel.rms file) as additional EVs in this confound EV file, it seems that a better option might be to use the fsl_motion_outliers script to generate these EVs (which then can presumably be added to the confound EV file). Is there any literature on the fsl_motion_outliers algorithm, perhaps comparing the performance of these two methods? Best, Jonathan Ipser Department of Psychiatry and Mental Health University of Cape Town