Dear Freesurfers,
Please see the attached image. It shows inflated fsaverage surface with gamma.mgh overlaid. Gamma.mgh is from one contrast of a standard group analysis of cortical thickness (two groups A and B, two contrasts A>B and B>A).
1) Is it correct to interpret the gamma values as between-group difference of cortical thickness in mm?
2) I would like to reproduce the histogram in another software. Is it possible to extract the gamma values for each vertex for this purpose?
All the best, Anders
On 10/08/2016 02:43 AM, Anders Hougaard wrote:
Dear Freesurfers,
Please see the attached image. It shows inflated fsaverage surface with gamma.mgh overlaid. Gamma.mgh is from one contrast of a standard group analysis of cortical thickness (two groups A and B, two contrasts A>B and B>A).
- Is it correct to interpret the gamma values as between-group
difference of cortical thickness in mm?
It depends on how you set up the contrast. If it is a simple A vs B, then yes, mm is correct.
- I would like to reproduce the histogram in another software. Is it
possible to extract the gamma values for each vertex for this purpose?
You can do it in matlab easily enough, eg, gamma = MRIread('gamma.mgh'); gamma.vol will be the pixel values
All the best, Anders
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
Excellent, thanks!
2016-10-12 20:27 GMT+02:00 Douglas N Greve greve@nmr.mgh.harvard.edu:
On 10/08/2016 02:43 AM, Anders Hougaard wrote:
Dear Freesurfers,
Please see the attached image. It shows inflated fsaverage surface with gamma.mgh overlaid. Gamma.mgh is from one contrast of a standard group analysis of cortical thickness (two groups A and B, two contrasts A>B and B>A).
- Is it correct to interpret the gamma values as between-group
difference of cortical thickness in mm?
It depends on how you set up the contrast. If it is a simple A vs B, then yes, mm is correct.
- I would like to reproduce the histogram in another software. Is it
possible to extract the gamma values for each vertex for this purpose?
You can do it in matlab easily enough, eg, gamma = MRIread('gamma.mgh'); gamma.vol will be the pixel values
All the best, Anders
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
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Anders Hougaard -
Douglas N Greve