Add terms for 'homotopic regions' #356
Description
This was originally raised in #104 and suggested as an UBERONParcellation.
Definition: Homotopic regions are areas in the left and right hemispheres of the brain that are in corresponding mirror positions and possess similar structures and functions.
This term seems to be largely used when their connectivity is being studied (i.e., 'homotopic connectivity' (synonym: 'homotopic functional connectivity'?)
I don't know how we could register the anatomical aspect of this, but I think there could be an analysis technique in there?