Dear Mozhdeh,
the size and orientation in the surface display do not matter. After resampling & smooth all images are in the same template space and can be statistically analyzed. However, your thickness data look very different. The large thickness values in the frontal areas look somewhat suspicious. Probably you might have large signal inhomogeneities in these areas. Please check image quality measures and sample homogeneity again.
Best,
Christian
On Thu, 10 Jun 2021 09:38:00 +0430, Mozhdeh Haddadpour <[log in to unmask]> wrote:
>Hello dear SPM experts,
>I implemented surface based morphometry analysis with the CAT12 toolbox but
>after statistical analysis I got "No Suprathreshold clusters' '.
>(condition: two sample t-test/ resample and smoothing size"164k/FWHM=15 for
>thickness data)
>On the other hand, when I displayed my resample&smooth thickness
>datasets for both control and patients group by using of "Display surfaces"
>in CAT12, I noticed that size and orientations of my resample and smoothed
>thickness datasets are not the same (only visually I noticed!!!!) Please
>check the attached figures.
>*Questions:*
>1.Can the differences in size and orientation of my "Resample and smooth"
>thickness data set be the cause of "No suprathreshold cluster" error??
>2. How can I manually or automatically change or check the orientation and
>size of the resample smoothed thickness datasets to be the same for
>statistical analysis?
>
>Thanks,
>Mozhdeh
>
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