Yes, just specify the age^2 as a covariate (in addition to the the linear trend). Add age^3 as well. Note that you should demean each, and probably rescale so that the max of each is 1.

Dalwani, Manish wrote:

Hi All,

If you don't have a linear trend in the Cortical thickness vs age correlation, is there a way to use a polynomial (quadratic, cubic) regression model to best fit the cortical thickness vs age using the GLM mechanism of freesurfer?

Regards, Manish Dalwani Sr. PRA Univ. of CO

---

---

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