|CENTERS OF IDEATION IN THE BRAIN.|
ON the 22d of February, 1887, Prof. David Ferrier delivered an address in this room on the question, "How far recent investigations on the functional topography of the brain could be brought in relation with craniological and anthropological researches with a view to establish the foundation of a scientific phrenology." It is my object to-night to continue that discussion, and to submit to you the basis of a scientific phrenology for your examination and criticism. I take it for granted:
1. That all mind-manifestation is dependent on brain-matter.
2. That the various elements of the mind have distinct seats in the brain, which, however, have not been as yet determined.
3. That the recent researches by physiological experimenters and pathological investigators—which have resulted in defining distinct regions for motion and sensation—established the physiological correlative of psychological actions.
By applying galvanic currents to definite portions of the brain, or by destroying certain areas, physiological experimenters cause movements of certain limbs and muscles. In itself the distribution of motor areas in the brain would be of little value to the psychologist except that it proves to him the plurality of functions of the brain. When, however, we observe that the movements caused by excitation form the physical parallel of a mental action, we may arrive at the psychological function of a certain portion of brain by reducing the various faculties of the mind to their elements, and watching their physical expression. No galvanic current will ever have the effect of demonstrating a center of ideation—say the center for the emotion of power; on the other hand, there are several emotions and all the higher intellectual operations, which have no outward physical signs. All which the excitation of that portion of brain where the emotion of power may have its center can effect is certain movements which such an emotion would cause when irritated.
To arrive, then, at the demonstration of centers of ideation there is but one way:
1. We must observe the physical expression of our thoughts and feelings, as far as possible; in other words, we must study the outward visible signs of their manifestation.
2. We must take the limbs and muscles, which are affected by definite emotions, and see on what occasions they are made to move by central excitation.
- A paper read before the Anthropological Institute, London, February 12, 1889.