WHEN CHARACTER IS FORMED. 



649 



Diagram B, from Starr, Atlas 

 of Nerve Cells, page 39, 

 modified especially to show 

 nucleus which is depleted 

 of energy when the cell is 

 in action. 



great amount of energy whicli may be expended in thought and 

 emotion, or which may issue directly in movement. Every one 



knows that a mere whisper of the death 

 of a dear friend or of an approaching 

 calamity or any similar circumstance will 

 create great mental disturbance and drain 

 the nerve cells to the point of exhaustion. 

 So the prick of a pin or a tickling of the 

 sole of the foot will produce vigorous 

 movements of the entire body in most per- 

 sons. It is probably true that in almost 

 all instances the physical or mental result- 

 ant of a given stimulus is far greater, from 

 the point of view of energy expended, than 

 the stimulus itself. Every stimulus enter- 

 ing the cerebral cells is re-enforced from 

 the energy stored therein ; and it is plain, 

 of course, that the less the supply or the 

 greater the demands made the more rap- 

 idly will exhaustion follow. In a study, 

 then, of brain fatigue in childhood we 

 have to consider first the conditions which determine the amount 

 of energy which shall be stored in the cells, which, as we shall 

 attempt to show, differs in individual cases on account of a variety 

 of varying circumstances ; and, secondly, we have to regard the 

 character of the work done, so as to notice how heavily it draws 

 upon the credit of the brain. 



It is the purpose here to consider especially the intellectual 

 and emotional concomitants of brain fatigue in childhood. In 

 order to ascertain these we may employ 

 any or all of several methods of inquiry. 

 In the first place, we may make direct 

 mental tests to determine if a child can 

 think as rapidly and logically in a state 

 of fatigue, occasioned by overwork or 

 by lack of food, as when refreshed after 

 rest or proper nutrition. In the second 

 place, we may by introspection observe 

 the effects of fatigue upon our own pro- 

 cesses of thinking and the character and 

 quality of our feelings. Third, we may 



study children in their everyday work and play, and observe the 

 influence upon their thinking and feeling of prolonged periods of 

 activity, of great excitement or overstimulation of any sort, of a 

 lack of proper and sufficient food, and other like conditions. 

 Again, we may by observation, and by experiment with apparatus, 



TOL. LI. i9 



-s-^ 



Diagram C. S = stimuli pour- 

 ing into the brain ( E ) through 

 all the senses, and issuing in 

 mental action or movement 

 (M). It shows that the ener- 

 gies of the brain are being 

 drawn upon continually to 

 re-enforce the stimuli from 

 the outer world. 



