Harris et al raise some important issues. First is the correspondence between their medial-frontal cortical' and our orbital-frontal2 areas, which they suggest are actually the same region (Brodmann areas 9 and 10). Our orbital-frontal extended from 3.2 cm to 4.8 cm above the orbital-meatal (OM) line on the right and from 3.2 cm to 6.4 cm above the OM line on the left. In contrast, in our calculation, their putatively similar areas extended from the level of the basal ganglia, about 6.4 cm above the OM line, to about 8.4 cm above the OM line. This is not to say that the two regions are completely separate; indeed, there may be some as yet undetermined degree of overlap that contains the area of increased 99Tm-HMPAO uptake.
Second is the question of scanner resolution. Harris et al suggest that their resolution, while one fourth that of ours (1.6 cm
Rubin RT, Mena I. Single Photon Emission Computed Tomography in Obsessive-Compulsive Disorder-Reply. Arch Gen Psychiatry. 1993;50(6):500–501. doi:10.1001/archpsyc.1993.01820180102017