Each frontal lobe, which consists of the tissue in the cerebral hemisphere lying anterior to the fissure of Rolando, may be divided into three major fields: the motor and the premotor area, already discussed by Bucy1and by Fulton and Viets2and the association area. The present communication concerns itself with the function of the association area; the terms "frontal association area," "frontal area" and "prefrontal area" are used interchangeably to designate that portion of the frontal lobe which lies anterior to the motor and the premotor area. It is nearly one hundred years since misfortune befell Phineas Gage and gave to neurologic literature the famous "American crowbar case." The functions of the frontal area and the disturbances of behavior ensuing from lesions of this so-called "silent" area, have continued to interest both the clinical neurologist and the student of cerebral physiology. The Italian neurologist, Bianchi,3has