104 



PHYSIOLOGY FOR NURSES 



and in receiving sensations from the skin and tissues. 

 This indicates that the amount employed in the mere 

 sensations of seeing, hearing, tasting and smelling is 

 equally small, and that the remainder of the cortex, a 

 very large portion of the whole, must be occupied, as 

 association areas in analyzing the sensations brought in 



I Corpus 



callosum 



Vision 



Olfactory 

 gustatory 



Pens] 

 Medulla oblongatal 



Fig. 25. Brain, mesial view. 



Cerebellum 



by these highly trained and developed nerves. Thus, 

 the uneducated may see a word as distinctly as the 

 trained, but it conveys no meaning, any more than would 

 a word in an unknown tongue. We can, therefore, read- 

 ily comprehend that we have not only memory for words 

 and their definitions, but that special areas of the brain 

 may be taught to preside over these functions and so 

 associate certain characters, which we call letters, with 



