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Hi - if this appears to have worked then it probably has!  However it's possible that your model-based confound removal *might* not have modelled the confound quite as well as ICA would have - so you could try that as well - i.e. use MELODIC and then fsl_regfilt.

Cheers.


On 29 Dec 2010, at 09:19, Jasper Looijestijn wrote:

> Dear Steve, 
> 
> Earlier I posted this message to the list, but did not get a response. Can you  inform me on this issue?
> 
> We are attempting to remove a 0.41 Hz noise artifact from our 4D BOLD fMRI data. The model that describes the artifact is:
> 
> EV1:
> 1 0 0 0 1 0 0 0 1 0 0 0 1 0 0 0…
> EV2:
> 0  1 0 0 0 1 0 0 0 1 0 0 0 1 0 0…..
> EV3:
> 0 0 1 0 0 0 1 0 0 0 1 0 0 0 1 0…..
> 
> We used the above design for  the <confound.mat>  used in the commandline script “unconfound” and applied the script to all our data. Is this a correct approach to remove the noise-artifact?
> On inspection of our unconfounded data we seem to have succeeded to a large extent. Does anyone have experience with the effects of this script on the data? Is there a downside to this approach we should be aware of?
> 
> With kind regards,
> 
> Jasper Looijestijn.
> 
> 


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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
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