BODY CONTROL AND HABIT FORMATION 353 



Functions of the Cerebrum. — In general, the functions of the 

 different parts of the brain in man agree with those functions 

 we have already observed in the frog. The cerebrum has to do 

 with conscious activity ; that is, thought. It presides over what 

 we call our thoughts, our will, and our sensations. A large part 

 of the area of the outer layer of the cerebrum seems to be given 

 over to some one of the different functions of speech, hearing, 

 sight, touch, movements of bodily parts. The movement of the 



^t^ Qioisr 



Cerebrum 



Cerebellum 



Medulla 



Spinal Cord 



Diagram to show the parts of the brain and action of the different parts of the 



brain. 



smallest part of the body appears to have its definite localized 

 center in the cerebrum. Experiments have been performed on mon- 

 keys, and these, together with observations made on persons who 

 had lost the power of movement of certain parts of the body, 

 and who, after death, were found to have had diseases localized 

 in certain parts of the cerebrum, have given to us our knowledge 

 on this subject. 



Reflex Actions ; their Meaning. — If through disease or for 

 other reasons the cerebrum does not function, no will power is 



HUNTER, CIV. BI. 23 



