On 5/2/2024 4:03 AM, yunus soleymani wrote:

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Hello freesurfers,

I have some questions about the output variables of Freesurfer:

1. In the case of brain volume normalization, do I need to normalize

all the volumetric results to the eTIV or just the subcortical volumes?

All volumes. And area too as you note in #4

2. Are there any formulas other than simple division in order to

normalize the volumes?

People will sometimes use eTIV as a regressor in the GLM instead of dividing (make sure to normalize so that the scale does not mess up the GLM)

3. How are the .ThckStd values (like FS_R_Insula_ThckStd) calculated?

What does the "std" mean here?

standard deviation across vertices

4. I believe that the surface area outputs are also affected by brain

size differences in the population. Are there any reference values in the Freesurfer outputs to which surface areas can be normalized?

I just use eTIV

Thank you in advance for your help.

Best regards, Yunus

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*Yunus Soleymani* ** *Ph.D. Candidate of Neuroimaging * /*Tehran University of Medical Sciences*/ /**/ /*MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be* *MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be* soleymani.yunus@yahoo.com http://secure-web.cisco.com/1m4nkPi6_buf-Yoy3fGn8mitMEiiTc-OBljMkHvwy8YuW66IDotA3jqMZZgU1aFeUFMubVIUEJ_Jooro8cUNQVi6bH2VYhiXL4hcOAt-ObKMPYv6UVchFfiKX5QVcr-wtS-YvTy-dcrLGJ5gcPbJEPmNlYnpMUJcOTEWKN3uos3L14QSREHGf2Bydw8QeaaHYF0D-iss-tPGBYzrYpIpQKwoeHt3pZtY3jtNjDoZ3-R8ufv4dhWjXIUkF6Wc2lrYzekO55ERXtjJUreXucqlOAbnOeLWJBVLrCIUoOQo3KSlBQCpLDKcLXWLO6NGYNhgGkZzi5oDwIzygmYxL74AkOg/http%3A%2F%2Fwww.yahoo.com/

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