Hi,
Did you apply the cleanup to the data after it had been through the
other preprocessing steps (motion correction etc.)?
If you used the Melodic GUI then there should be a file called
filtered_func_data in the original .ica output directory, and you
should be feeding THAT preprocessed image into the cleanup.
Does this help resolve things?
Cheers, Steve.
On 15 Mar 2007, at 15:12, Timothy Laumann wrote:
> Dear FSLlist,
>
> I have been trying to use the filter option to remove noise from my
> data and
> I am wondering how exactly the function works. I thought that the
> filter
> function was merely removing the specified components from the
> mixing matrix
> and rebuilding the data sans those components. Just to see what would
> happen, I filtered 25 of the 50 components generated from a 200
> image dataset,
>
> melodic -i data.hdr -v -o filtered_data.ica --mix=melodic_mix -f
> "2,3,.."
>
> and then performed a melodic ICA on the filtered_data.img that is
> created.
> I expected to get the 25 remaining components only, but instead
> still got
> close to 50 components. Clearly there is something about this
> process that
> I do not understand.
> Thanks for the help!
>
> Tim
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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
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