 |
 |
Dear Vladimir, You could include a regressor in your GLM design matrix that describes this condition. Then, when you come to extract the data using the VOI tool, use a contrast which does not span that condition. This will result in this effect effectively being subtracted from the data - DCM will not try to explain it. Best, Will. Vladimir Cherkassky wrote: > Dear DCM experts, > > In a DCM fMRI experiment, we need to exclude one of the experimental > "conditions" from the DCM analysis (some subjects did not perform the task > properly). What would be the right way to do this? > > I would greatly appreciate any advice. > > Thanks in advance, > > Vladimir Cherkassky > Center for Cognitive Brain Imaging > Psychology Department > Carnegie Mellon University > Pittsburgh, PA 15213 > email: [log in to unmask] > fax: (412) 268-2804 > tel: (412) 268-3379 > > -- William D. Penny Wellcome Department of Imaging Neuroscience University College London 12 Queen Square London WC1N 3BG Tel: 020 7833 7475 FAX: 020 7813 1420 Email: [log in to unmask] URL: http://www.fil.ion.ucl.ac.uk/~wpenny/