5 1 4 THE POPULAR SCIENCE MONTHLY. 



CENTERS OF IDEATION IN THE BRAIN.* 



By BERNAED HOLLANDER. 



ON the 22d of February, 1887, Prof. David Ferrier delivered an 

 address in this room on the question, " How far recent inves- 

 tigations on the functional topography of the brain could be 

 brought in relation with craniological and anthropological re- 

 searches 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 physio- 

 logical 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 distribu- 

 tion of motor areas in the brain would be of little value to the 

 psychologist except that it proves to him the plurality of func- 

 tions of the brain. When, however, we observe that the move- 

 ments 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 gal- 

 vanic 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. 



