A large corpus of data a both the animal and human levels implicate various sectors of the PFC in emotion. The PFC is not a homogeneous zone of tissue, but rather has been differentiated on the basic of both cytoarchitectonic as well as functional considerations. The three subdivisions of the primate PFC that have been consistently distinguished include the dorsolateral, ventromedial, and orbitofrontal sectors. In addition, there appear to be important functional differences between the left and the right sides within each of these sectors.