Dear all,

We are modeling changes in cortical thickness over time using a cross-sectional design.  We have two groups of participants, age 8 to 18.  In the cortical regions that interest us, there is generally a linear decline in thickness with age.  Each group can be fitted to a best-fit line.  The question we are interested in is whether there is a significant difference in thickness between groups at a given age (i.e., not just collapsed across age) — specifically, at the earliest age point (age=8).  Is this possible to model across the brain surface in Freesurfer?

Thanks,

Hamdi and Josh