THE CEREBRUM AND HUMAN DEVELOPMENT 145 



"central vision," which is of the foremost importance, is 

 bound to survive, thanks to the reduplicated projection in 

 the cortex. 



The auditory path leads first to the medulla and thence, 

 by repeated relays, to the cerebrum. The best marked 

 projection of the impulses from the organ of hearing is 



Fig. 23. The upper figure represents the left hemisphere from 

 outside, that is, from the left. The lower figure shows the internal 

 or mesial aspect of the right hemisphere, that is, the right hemisphere 

 from the left side. Areas usually claimed to possess special relations 

 are marked as follows: H, hearing; V, vision; Sm, smell; Sp, speech. 



upon the cortex of the temporal lobe, and damage to this 

 part has often caused deafness. The effect is to impair 

 more considerably the reactions from the opposite ear, 

 though some limitation is imposed upon the usefulness of 

 the ear of the same side. An area for the reception of im- 

 pulses of olfactory origin is said to be well set off. Ii 

 10 



