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Hi On Wednesday, Oct 15, 2003, at 02:41 Europe/London, nima dehghani wrote: > hi > > we used FSL-MELODIC to extract "independent components" of our "10 > subject trial"; in each trial, subjects experienced 2 conditions (A > and B)...as a part of our analysis, we need differences of BOLD > response between A and B! > so: > > is it possible to use ICA to compare difference between 2 condition? > or it will only give us components that we should check whether they > have the similar timing pattern to condition A? or condition B?,... > Melodic will give you a representation in terms of spatial maps and associated time courses where the decomposition is found such that individual spatial maps are statistically independent. If this is also true for the cortical areas involved in processing under your two different conditions, then ideally melodic should generate separate component maps with associated time courses that match the A resp. B timing (the audio/visual stimulation data set which comes with FEEDS is an example of this) If the cortical areas involved are overlapping, the decomposition could, however, be different to what you'd like to see (Calhoun et al. "Spatial and temporal independent component analysis of functional MRI data containing a pair of task-related waveforms" Human Brain Mapping, 2001 give an example of this) and yes, you should always check what you get ta christian > > cheers > > > Nima Dehghani MD. > > Schizophrenia, Cognition and Imaging Labaratoy; Department of > Psychiatry; UBC; CA > Email: > [log in to unmask], [log in to unmask] > > -- > __________________________________________________________ > Sign-up for your own personalized E-mail at Mail.com > http://www.mail.com/?sr=signup > > CareerBuilder.com has over 400,000 jobs. Be smarter about your job > search > http://corp.mail.com/careers