This volume presents the proceedings of yet another symposium, this one held at Pennsylvania State University in August, 1962. Participants included neuroanatomists, neurophysiologists, psychiatrists, and psychologists, chiefly from the United States, all specialists in the general area of brain and behavior. The purpose of the symposium was to describe and evaluate the more recent research on the structural and functional evolution of the so-called prefrontal lobes in mammals.
Readers of this symposium might evaluate the alleged advances in understanding in relation to two previous landmarks. As pointed out by Konorski and Lawicka, "The discovery made by Jacobsen (1936) establishing that delayed responses . . . are severely impaired after prefrontal lobectomies in monkeys may be considered as a milestone in research concerning the functions of prefrontal areas. It is true that much discussion has developed around the question of how Jacobsen's findings should be explained; however, the fact itself has been