Hi, the modulation is derived from the warp field that got the image
from native space to standard space - so the answer would depend on
whether you have those and in what form. I suspect that you will only
be able to achieve this if you go through the whole FSL-VBM chain or
the whole SPM-VBM chain.
Cheers.
On 3 Mar 2008, at 19:57, Jane Zhang wrote:
> Hi,
>
> Sorry about my simple question--I have over 150 unmodulated gray
> matter images which are registered to a sample-specific template and
> I need the modulated MRI images for VBM analysis. I'm trying SPM5
> segmentation (which generates modulated and unmodulated images), but
> it takes long long time to run. I'm wondering whether there is a
> quicker way to obtain modulation matrix (the Jacobian of the warp
> field) in FSL (since FSL is written in C++, it runs faster). It
> seems that fslvbm_3_proc does modulation. Can I get modulation
> matrix from fslvbm_3_proc for each registered gray matter image?
> Then, the unmodulated image can be divided by the modulation matrix
> to get modulated gray matter image. Please let me know.
>
> Thanks in advance for your help,
>
> Jane
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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)
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