Hi All,
I used DARTEL to warp all of my functional data to a group-specific template
and did a second level analysis with really nice results. However, now I
want to redo the analysis in MNI space so I can properly identify MNI
coordinates of regions of interest.
In the analysis I did initially in group-specific space, I did:
1. Segment anatomicals
2. Initial Import
3. Run DARTEL (create Templates) - using grey and white segments
4. Create Warped (using contrasts from 1st level analysis (con_0001.img) and
corresponding
flow fields u_rc*)
5. Smoothed the resulting warped contrasts (in group-template space) with
5mm kernel
6. Ran 2nd level analysis on smoothed, warped contrasts.
This looked great, but since I'd like to overlay the results on an MNI
brain, I instead tried to use "Normalize to MNI Space" using the flow fields
I created previously (u_rc*) and
the contrasts I used previously (con_0001.img) as well. Before I did the
analysis, I
looked at the results of these steps to make sure the images looked
reasonable and I'm attaching the results.
Upper left is the group-specific template.
Upper right is the contrast warped to the group-specific template with DARTEL
Lower left is the contrast normalised using Normalise (Estimate and Write)
Lower right is the contrast normalised using DARTEL's Normalise to MNI Space
(the one I'm worried about)
Any idea why there are flowery blobs around the contrast when it is
normalised to MNI with DARTEL? I would really like to use DARTEL so I can
invert the transformation and look at the significant group-level regions
back in each subjects' native space, so any help would be greatly appreciated.
Thanks!
Brianna
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