It's a "volume" files with about 160000 values. If you know which vertex you want, you can load it into matlab with MRIread.m

On 3/11/12 1:44 PM, Knut J Bjuland wrote:

Hi Doug

Could you please explain how I can extract the standard deviation in

rstd.mgh? Should I use mri_info or matlab?

Knut J

On 10. mars 2012 23:17, Douglas Greve wrote:

...

Hi Knut, you will need the effect size which is gamma/rstd where rstd is the the standard deviation of the noise which is stored in rstd.mgh in the glm directory. doug

On 3/10/12 10:35 AM, Knut J Bjuland wrote:

...

Dear Sirs/Madams

How to access information in gamma.mgh and gammavar.mgh? Which command should I use? Since it not explained in the tutorial. I want to use it to calculate effective population size? How large population size is needed to demonstrate a deviation between to population in cortical thickness?

Best regards

Knut J _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

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