hi, let's say i have a gray matter mask such as the one output by FAST tissue segmentation, and instead of using some bulky MNI labels or freesurfer to segment the cortex, i want to just chop it up into say n small regions, call these my 'micro-rois' (i would want ~500-1000).

also, i want to classify each region according to its distance from a certain reference point, say, the thalamus ... so the 'value' of each micro-roi would be the distance in i,j,k, from the thalamus.

does anyone know how i might go about this in afni? to recap, i want to partition a gray matter mask into 500-1000 small rois, and assign each of those rois a value based on its distance from a fixed reference point.

oh and incidentally, does anyone know how to get the 'center of mass' of a certain roi, in i,j,k coordinates?

thanks,

Russell