Some Observations on the Functional 

 Organization of the Human Brain 



By Wilder Penfield 



Director, Montreal Neurological Institute 



Professor of Neurology and Neurosurgery 



McGill University 



[With 1 plate] 



In Proverbs it is written : "For as he thinketh in his heart so is 

 he," and again in the New Testament a thousand years later at the 

 time of the birth of Christ, "Mary kept all these things and pondered 

 them in her heart." It was only yesterday that Vannevar Bush 

 slipped back into the same manner of speaking : "The seat of ethics," 

 he said, "is in our hearts, not in our minds." (I'm sure he must be 

 flattered by the succession in which he thus appears!) 



But in the Elizabethan era even Shakespeare spoke otherwise, re- 

 ferring to the "brain which some suppose the soul's frail dwelling 

 house." Medical men had by that time come to consider the brain to 

 be the organ of the mind, believing that it functioned in some mys- 

 terious manner as a whole without localization and specialization of 

 functions. Even today, although we are awed and even frightened by 

 the intellectual achievement of man's mind, the mechanisms that make 

 it possible are still unknown. 



Knowledge of the outward form of the brain is well advanced. 

 The pathways of sensation and of movement within the brain have 

 been, and are being, charted. But what of the neurone mechanisms 

 involved in consciousness, perception, memory. Far off, it seems to 

 me, we hear the humming of the machinery of the mind and from 

 time to time, we gain fleeting glimpses of its action. But still we stand 

 in awe upon the threshold of understanding. I shall describe certain 

 glimpses that have come to me by patience and by good luck. 



But first I must make reference to what is common knowledge of 

 the human brain (pi. 1 ) . The mechanisms of reflex movement are well 



* Reprinted by permission from Proceedings of the American Philosophical 

 Society, vol. 98, No. 5, October 1954. 



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