Approximately a thousand articles have appeared in medical and psychologic journals within the past forty years on the subject of the psychogalvanic reflex. Until recently the fact that the resistance of the human skin to the passage of imperceptible electric currents was decreased following certain psychic stimuli was looked on as an important objective means of measuring emotion, and many investigators advocated the use of this phenomenon in the study of the neuroses and the major psychoses. Unfortunately, earlier investigators were handicapped by a lack of knowledge concerning the physics and physiology of the reflex, the result being that experiments were usually poorly controlled and the findings of different workers were often contradictory. Landis1 stressed the chaotic state of the literature in this field and concluded that "there is no good and sufficient reason, except that of historical fallacy, why one should continue to hold that the 'psychogalvanic reflex'