Hi - it's difficult to judge registration quality by looking at the
activation overlay - you should be clicking on the registration evaluation
image towards the bottom of the FEAT webpage report and look at the
detailed registration evaluation images - do they look ok?
Cheers, Steve.
On Mon, 17 May 2004, Jane Aspell wrote:
> Hi
>
> I'm having some problems registering my functional data onto a highres
> image of an individual subject's brain. My functional data is in the form
> of 24 obliquely oriented slices mainly covering the occipital area (it's a
> vision study). The clusters of activation seem to 'flame out' from the
> brain in some areas, into 'space' by a few millimetres. This problem seems
> to be worse in occipital areas and not so bad in parietal areas. I have an
> idea that occipital areas are subject to more distortion than other areas -
> is this true? To register my functional to a highres with flirt i did a 7
> parameter global rescale transformation from my 24 slice functional
> data to a 120 slice EPI (slices at the same angle as the functional) and
> another 7 param global rescale to my individual highres structural. is
> there anything you could advise i do to improve my registration?
>
> many thanks for your time,
>
> Jane Aspell
>
Stephen M. Smith DPhil
Associate Director, FMRIB and Analysis Research Coordinator
Oxford University Centre for Functional MRI of the Brain
John Radcliffe 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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