Hi Martina,
before trying to implement the FSL-VBM longitudinal protocol, which requires an intermediate/advanced knowledge of FSL tools and commands, I would strongly suggest you to:
1) try the "classic" protocol, as this produces *perfectly valid, unbiased results*
2) if you really think that your study would benefit from the longitudinal protocol, try first to familiarise yourself with the FSL tools by going through the relevant practicals of the FSL course (http://www.fmrib.ox.ac.uk/fslcourse/)
To answer briefly your questions, you would need to use either flirt or applywarp to apply the *.mat to your images, and fslmaths to average them in the halfway space.
Hope this
helps,
Gwenaëlle
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Gwenaëlle Douaud, PhD
FMRIB Centre, University of Oxford
John Radcliffe Hospital, Headington OX3 9DU Oxford UK
Tel: +44 (0) 1865 222 523 Fax: +44 (0) 1865 222 717
www.fmrib.ox.ac.uk/~douaud
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De : Martina Diamandis <[log in to unmask]>
À : [log in to unmask]
Envoyé le : Lundi 5 Décembre 2011 16h31
Objet : Re: [FSL] Re : [FSL] AW: [FSL] AW: [FSL] AW: Is there an FSL-VBM for longitudinal studies yet?
Hello!
I just started trying to run a longitudinal VBM analysis and have a very basic question (but couldn't find an answer yet):
Gwenaelle wrote about a longitudinal VBM:
"1) determine the halfway transformation (as in Siena) between the two timepoints for each subject (a priori 6DOF)
"2) register both timepoints to this halfway space, average them, the bet the average
..."
So I started using SIENA and I assume the transformation I need are "A_halfwayto_B.mat" and "B_halfwayto_A.mat", right? But how do I register both timepoints to this halfway space? And in particular, how do I average them? I simply have no clue...
Any help is highly appreciated!
Many greetings from Scotland!