One sample t-test results of ReHo

Submitted by Yangmei Luo on

Hi RESTers,

I have a question on the one-sample t-test results using ReHo method. We obtained the results using DPARSFA and fed those files whose initial name is sm into one-sample t-test in REST. However, I found the whole brain was ‘activated’, although the results have been corrected by FDR. It is still the same even if I employed more rigorous comparison correction method. Is there any problem in the process of the analysis? How could I deal with such a problem?

Thank you in advance for you kind help. Any help is appreciated. 

Yangmei Luo

YAN Chao-Gan

Sun, 09/29/2013 - 11:21

Hi Yangmei,

You are using SPM to do one-sample t-test on sm*ReHo* maps? Or you are using REST? And if the latter, which base you choose? "0"?

For sm* maps, you should compare with 1 (i.e., one-sample t-test against base 1), to see if a voxel is significantly bigger than the brain mean value.

Also, if you are using z* maps (Z-standardization), usually you will compare with base "0".

BTW, there are some comparisons of standardization methods in: Yan, C.G., Craddock, R.C., Zuo, X.N., Zang, Y.F., Milham, M.P., 2013. Standardizing the intrinsic brain: towards robust measurement of inter-individual variation in 1000 functional connectomes. Neuroimage 80, 246-262.



Hi Chao-Gan,

Thank you for your quick response. It is really helpful. Actually, I using REST and sm*maps. Thank to your suggestion, I compared the maps with base "1", the problem has been solved. 

Thank you so much!  I appreciated that.


Yangmei Luo