AFNI Message Board

History of AFNI updates  

July 30, 2018 11:26AM
Hi Mariana-

You can use either 3dTcorr1D or 3dttest++ (or if you want to go super old school, 3dRegAna).

If you want to use 3dTcorr1D, you can follow instructions here.

If you'd prefer to use 3dttest++, then you can follow the instructions here.

The nuance of 3dttest++ is to then use 3dcalc to convert the t-value to a correlation via the t to R-square method.

3dcalc -a T-stat+tlrc -expr ‘(ispositive(a)-isnegative(a))*sqrt(a*a/(a*a+DF))’ -prefix corr

The two programs will provide identical results, it's ultimately about what you're most comfortable using. If you have a series of behavioral measures, you'll need to do either of these processes in a loop, but you can use column selectors to grab the correct variable to correlate with the MRI data. 3dttest++ will figure out the matching data file, whereas 3dTcorr1D, the MRI and behavioral data must be in the same order.
Subject Author Posted

Simple brain - behavior correlation

mterrateixeira July 30, 2018 10:42AM

Re: Simple brain - behavior correlation

Peter Molfese July 30, 2018 11:26AM

Sorry, only registered users may post in this forum.

Click here to login