76 



THE NERVOUS SYSTEM 



the localisation of function, so far as the highest 

 centres of the nervous system were concerned. In 

 that year Fritsch and Hitzig discovered that 

 electrical excitation, with minimal stimuli, of various 

 points of the cortex, caused those storehouses, of 

 which Willis spoke, to discharge, and to reveal 

 their function by the precise limitation of the groups 

 of muscles which they were able to throw into 

 action. These researches were abundantly con- 

 firmed and greatly extended by Professor Ferrier, 

 and thus has been constructed in the history of 

 this subject the most recent great platform or stage 

 of permanent advance." # 



Hitzig gives the following summary of his 

 results : — 



" A part of the cerebral surface, in the dog, is 

 motor ; another part is non-motor. 



" The motor part lies, roughly speaking, more 

 anteriorly ; the non-motor part lies more posteriorly. 

 By electrical stimulation of the motor part, one 

 obtains combinations of muscular contractions on 

 the opposite side of the body. 



" These muscular contractions, by the use of very 

 weak currents, can be localised to certain definite 

 groups of muscles. With stronger currents, which 

 stimulate similar or contiguous regions, other 

 muscles are involved, and even the corresponding 

 muscles of the trunk. The isolated stimulation of 

 a limited group of muscles can only be made 

 possible by the use of very weak currents over 

 very small areas, which we will call centres for the 

 sake of brevity." 



* Horsley, Fullerian Lectures, 1891, loc. cit 



