THIS PAPER presents a simple, unifying theory of the function of the frontal lobe. The theory was developed in 1946 and first presented orally at the meeting of the American Psychiatric Association in 1949 as part of my comments on a paper by Hoch.1 At that time the hypothesis was well received by the audience, and encouragement was given me to develop it further and to find supporting evidence, which I present here for the first time in written form.
I. THE THEORY
The theory which describes what may be called briefly the persistence function of the frontal lobes is as follows (the term "frontal lobes" is used in this paper in a limited sense to refer specifically to Brodmann areas 9, 10, and 11 and to Walker's modification of Brodmann areas 13 and 14): The frontal lobes do not have a primary function, such as the mediation of