Hi,
> When we want to analyze fMRI images of a subject, after realignment of
> fMRI images, we can first coregister them with an MRI image of the same
> subject, Segment the coregistered MRI with prior probabibility images
You could possibly tune this sequence by using the mean EPI and by
segmenting the anatomical and then coregistering to the GM map instead
(which reduces the influence of non-brain tissue).
> and then aplly the deformation fields (used for warping prior images)
> obtained in segmentation process on the realligned fMRI data and proceed
> with GLM. Can anybody tell me what is the result of applying deformation
> fields on fMRI data and why should it be performed?
The effect is: your data will be normalized :)
OK, more seriously: the warps that are estimated during the segmentation
process are written out in two ways: one, warp the priors to the
original image (seg_sn_inv or so) and two, warp the original to the
priors. As the priors are in MNI space, this effectively normalizes your
original image and consequently, all that are in alignment with it. You
can apply them by selecting Normalize, write normalized only, select the
seg_sn parameter file and apply to the functional series.
> Thanks
Sure :)
Marko
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Marko Wilke (Dr.med./M.D.)
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Universitäts-Kinderklinik University Children's Hospital
Abt. III (Neuropädiatrie) Dept. III (Pediatric neurology)
Hoppe-Seyler-Str. 1, D - 72076 Tübingen
Tel.: (+49) 07071 29-83416 Fax: (+49) 07071 29-5473
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