CEREBRAL LOCALIZATION 



853 



toms. In order to discover the exact function of these areas, it has been 

 necessary to employ an entirely different method that of histologic 

 and embryologic examination. When the patterns of the gray cortex 

 are compared with the habits of the animals, in different groups of 

 animals (phylogenetic study), or even in different individuals of the 



Fig. 221. The location of the chief motor and sensory areas on the outer (A) and mesial (B) 

 aspects of the human brain, as determined by the microscopic structure of the cortex. These 

 maps are only approximately accurate, but they indicate in a general way how the cortex is 

 structurally composed. (From Starling after Campbell.) 



same group (ontogenetic study), much useful knowledge concerning 

 cerebral localization can also be gained. In the human animal much 

 progress is being made by comparing the structural pattern of the cor- 



