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Hi, Yes - I think you're right the manual doesn't mention these. These are the temporal and subject modes in a tensor decomposition (which you didn't do). If you choose the temporal concatenation approach (which you did) they are slightly harder to interpret - basically the long timecourse from melodic_mix (ie the ICA timecourse for a given component) is reorganised into a timeXsubjects matrix and PCA is run, and that's what gives the Tmodes and subject weightings - or something like that....Christian knows the details ;-) Cheers. On 20 Apr 2009, at 09:34, M Mather wrote: > Perfect - that is just the information I was looking for. Thanks so > much! > > Out of curiosity, what do the columns in the melodic_Tmodes > correspond with? > I apologize if I am asking something that is detailed in a manual > somewhere > - I have been searching for information on what the output files > correspond > with but have not been able to find it. > > On Mon, 20 Apr 2009 09:15:17 -1000, Steve Smith > <[log in to unmask]> wrote: > >> Hi - you want the file melodic_mix which contains a column for each >> ICA component, and each column is the concatenation across time of >> all >> subjects' temporal chunks of that component's full timecourse - so >> split that up vertically and then you can compare that data >> separately >> for each subject against their own model. I guess they are demeaned >> so >> the model will also need to be. >> >> Cheers. >> >> >> >> On 20 Apr 2009, at 04:55, SUBSCRIBE FSL Anonymous wrote: >> >>> Sorry, I meant to ask what the output file melodic_Tmodes saves. It >>> has as >>> many rows as there are volumes in my analysis, so it seems to be the >>> time >>> series, but although the number of columns increases as the number >>> of >>> sessions entered in the analysis increases, it is not a clear >>> correspondence >>> between the number of columns and the number of sessions (e.g., 234 >>> columns >>> for an analysis with 72 sessions that yielded 15 components). >>> >>> thanks, >>> Mara >>> >>> On Mon, 20 Apr 2009 15:34:25 +0100, M Mather <[log in to unmask]> >>> wrote: >>> >>>> I have run a group ICA using the concatenation mode and have what >>>> looks like >>>> a meaningful set of components. However, we counterbalanced task >>>> block order >>>> across subjects and so cannot use the built-in post-stats options >>>> to >>>> correlate the components with what the subjects saw. Is there some >>>> other >>>> way we could compute a correlation between the time course of a >>>> particular >>>> component for a subject and the conditions that subject saw over >>>> that time >>>> course? It seems that we might be able to use the output files >>>> from the >>>> analysis if there is a text file in which each subjects' time >>>> course for >>>> each component was saved. >>>> >>>> Related to this, what is the information saved in melodic_Smodes? >>>> I can't >>>> figure it out since the number of columns is not divisible by >>>> either the >>>> number of components or the number of sessions. >>>> >>>> Many thanks for your help, >>>> Mara >>> >> >> >> --------------------------------------------------------------------------- >> Stephen M. Smith, Professor of Biomedical Engineering >> Associate Director, Oxford University FMRIB Centre >> >> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK >> +44 (0) 1865 222726 (fax 222717) >> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve >> --------------------------------------------------------------------------- > --------------------------------------------------------------------------- Stephen M. Smith, Professor of Biomedical Engineering Associate Director, Oxford University FMRIB Centre FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK +44 (0) 1865 222726 (fax 222717) [log in to unmask] http://www.fmrib.ox.ac.uk/~steve ---------------------------------------------------------------------------