CEREBRAL LOCALIZATION. 599 



front the theorist when he applies himself to practical work with per- 

 sonal responsibility, and he begins to find that the means at his disposal 

 are inadequate to the results exj)ected from him. 



CEEEBKAL LOCALIZATION ; OR, THE NEW PHRE- 

 NOLOGY.* 



By HENKY DE VAEIGNY. 



" TTTHEN the one who listens does not comj^rehend, and the one 

 VV who speaks understands as little, you have metaphysics," 

 says Voltaire. Taking this as a true definition, we may say that there 

 has been, and yet remains, much metaphysics in the treatment of the 

 functions of the brain. But the difficulties in cerebral physiology are 

 great. There is divergence of hypotheses, the facts themselves are 

 not settle.d, and contradictions abound. The foundations of the sci- 

 ence are yet deficient. But it does not follow that experiments are 

 useless. For half a century important researches have been carried 

 on ; and more recently facts have been discovered to which we would 

 here draw attention. 



From an anatomical point of view the brain is composed of two 

 symmetrical halves, right and left, united by a voluminous commis- 

 sure, which probably puts into communication the homologous parts 

 of the two hemispheres. Each hemisphere consists of a central mass, 

 Avith its envelope of convolutions. The central mass, partially sepa- 

 rated from its outer covering by the lateral ventricles, is composed of 

 two round bodies, formed of gray nerve-cells the active part of the 

 nervous system. The office of these rounded ganglia seems to be to 

 strengthen the impressions that come from without, or from stimu- 

 lated parts of the brain itself, and they may take part in automatic 

 actions. They are in relation, on the one hand, with the spinal cord, 

 and perhaps, more or less directly, with most of the motor and sensi- 

 tive fibers of the body ; on the other hand, they are connected by 

 fibers with the gray matter which is sj^read out in layers over the con- 

 volutions of the brain. In other words, the nerve-cells forming the 

 periphery of the convolutions give out white fibers, which penetrate 

 the central ganglia, probably connecting themselves with their cells. 

 From these cells other fibers proceed toward the cord and extremities 

 of the body. The central masses are on the line of the cerebral fibers 

 between their origin in the gray cells of the convolutions and their 

 termination in the cord and body generally. 



* Translated and abridged from the " Revue des Deux Mondes " by Miss E. A. You- 

 mans. 



