Hi,
the easiest way is to add confound regressors into yur design matrix,
i.e. for each volume you'd like to remove simply add a separate EV
which is 0 everywhere and 1 for the volume you want to remove -
obviously you don't want to convolve these nuisance EVs and also
don't want the temporal derivatives. These EVs then effectively
remove these volumes from contributing to the model fit (parameter
estimates) without actually cutting the data into pieces.
hope this helps
christian
On 23 May 2007, at 19:10, Deborah Shiloff wrote:
> Hello
>
> I have some data that contains a lot of motion artefacts. I would
> like to
> use the motion information generated from McFlirt to remove volumes in
> which the subject was seen to move excessively.
>
> Is there an existing tool to perform this operation or do I have to
> write
> my own code to do this?
____
Christian F. Beckmann
University Research Lecturer
Oxford University Centre for Functional MRI of the Brain (FMRIB)
John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK.
[log in to unmask] http://www.fmrib.ox.ac.uk/~beckmann
tel: +44 1865 222551 fax: +44 1865 222717
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