28O APPLIED PHYSIOLOGY 



the body. The peculiar sensations which tell a man that 

 he is beginning to fall pass to the cells of the cord, and 

 they in a reflex way send out the proper orders for the 

 muscles to put the body in an upright position again. 



506. Reflex action in education. The reflex action of 

 the spinal cord can be educated. Even a simple reflex 

 action like standing must be learned. When a baby first 

 tries to walk, his brain cells give the proper orders to the 

 cells of the spinal cord, and they in turn give them to the 

 muscles. Thus he slowly directs each detail of the move- 

 ments with his brain. Soon the spinal cord learns to send 

 the next order as soon as it feels the sensation of the 

 previous movement, and finally all the movements needed 

 become reflex, and the child runs about with but little 

 effort on the part of his brain. 



In learning to play a piano, the brain is occupied both in reading 

 the notes and directing the movements of the fingers in playing. 

 But, at last, the brain has only to read the notes to the cord and it 

 instantly sends the proper orders that they be played. 



Education and skill in any art consist in the ability of the cord to 

 execute proper movements while the brain is wholly occupied with the 

 design. In this ability to acquire new uses, the cells of the nervous 

 system differ from all other cells of the body. When the hand is 

 educated, it is really the spinal cells which are educated. 



507. Excessive reflex action. Reflex acts are some- 

 times not beneficial. A slight noise gives some people a 

 fright, and in lockjaw the slightest sensation causes the 

 spinal cells to send out orders for the muscles of the body 

 to contract violently. Self-control is largely the power 

 which the brain has of restraining the spinal cells from 

 sending out orders even when strong and sudden sensa- 

 tions are received. Thus, when something tickles the 

 throat, it is possible for the brain to restrain the spinal 



