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HANDBOOK OF PHYSIOLOGY. 



the tip of the uncinate convolution, causes torsion of the lip and nostril 

 of the same side. 



It is thus seen that the motor areas chiefly correspond with the 

 ascending frontal and ascending parietal convolutions, and. that the 

 movements of the leg are represented at the upper part of these con- 

 volutions, then follow from above downward the centres for the arms, 

 the face, the lips, and the tongue. 



According to the further researches of Schafer and Horsley, electrical 

 stimulation of the marginal convolution internally at the parts corre- 

 sponding with the ascending frontal and parietal convolutions, from 



Fig. 380. Fig. 381. 



Figs. 380 and 381. Diagrams of monkey's brain to show the effects of electric stimulation of cer- 

 tain spots. (According to Ferrier.) 



before backward, produces movements of the arm, of the trunk, and 

 of the leg. 



A good deal of doubt was thrown upon the experiments of Ferrier 

 by Goltz and other observers, from the results of excising the so-called 

 motor areas of the dog's brain. It was found that the part might be 

 sliced away or washed away with a stream of water, but that no perma- 

 nent paralysis en sued. 



More extensive observations however, have confirmed Ferrier's original 

 statement, at any rate with regard to the monkey's brain. Destruction 

 of the motor areas for the arm produces at any rate some permanent 

 paralysis of the arm of the opposite side, and similarly of that for the : 

 leg, paralysis of the opposite leg. If both areas are destroyed permanent 

 hemiplegia ensues. Paralysis of so extensive and permanent character 



