XXIII. BODY CONTROL AND HABIT FORMATION 



Problems. — How is body control maintained ? 



(a) What is the mechanism of direction and control? 



(b) What is the method of direction and control ? 



(c) Wh at are habits ? How are they formed and how brohen ? 

 id) What are the organs of sense ? What are their uses ? 



(e) How does alcohol affect the nervous system? 



Laboratory Suggestions 



Demonstration. — Sensory motor reactions. 



Demonstration. — Nervous system. Models and frog dissections. 



Demonstration. — Neurones under compound microscope (optional). 



Demonstration. — Reflex acts are unconscious acts ; show how con- 

 scious acts may become habitual. 



Home exercise in habit forming. 



The senses. — Home exercises. — (1) To determine areas most sensitive 

 to touch. (2) To determine or map out hot and cold spots on an area on 

 the wrist. (3) To determine functions of different areas on tongue. 



Demonstration. — Show how eye defects are tested. 



Laboratory summary. — The effects of alcohol on the nervous system. 



To the Teacher. — The purposes of the following exercises are first, to show 

 the pupil that he is dependent upon his organs of sense in order to interpret what 

 goes on about him, thus to get in touch with the factors of his environment ; second, 

 to give him a glimpse of the great complexity of the mechanism and complicated 

 structure we call the nervous system ; third, to show him how habit might be 

 evolved and the part habit plays in our daily life ; and lastly, a slight conception 

 of the workings of the organs of sense, as shown by experimental psychology. 



Problem 220 : How are we aware of the world about us ? 



Materials. — Needle, ether or freezing mixture for local anaesthe- 

 sia, various substances having distinct taste. 



Method and Observations. — Touch a flat and a rough surface 

 with the finger tips. 



Prick yourself with a needle. Then place a drop of ether or 

 freezing mixture on the same finger and prick it. Do you still 

 feel? How do you explain the difference? 



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