Oh, I just thought of another thing. In high school, my husband was diasgnosed with what he calls 'lateralidad', which I haven't been able to find much about but sounds like something to do with brain function and lateralization. I don't know how much of this is genetic, but if gestalt thinking is about right brain dominance, maybe there's something like my husband's diagnosis going on with DD. Hubby, however, still tested PG despite his 'laterality'.