THE EDUCATION OF THE NERVOUS SYSTEM. 347 



cells are far beyond the limits of their ordinary per- 

 formance. It will serve to suggest the latent possi- 

 bilities of this sort resident in the central system if 

 we recall the strength of very moderately developed 

 men suddenly exhibited during attacks of maniacal 

 frenzy. 



In all functional activities a tendency to the formation 

 of habits occurs. Concerning these associations there is 

 one feature of much educational importance, generally 

 recognised, to be sure, but which at the same time has 

 been made more clear by the investigations of Berg- 

 strom. 1 In these experiments the test was to sort as 

 rapidly as possible, and according to suit, a pack of 

 cards, placing them in piles on a table. Another pack, 

 with the cards in a different order, was then taken, and 

 the experiment repeated. This second trial took much 

 longer than the first. The increase in the time was 

 found to be due, not to fatigue, but to certain associa- 

 tions formed during the first sorting, whereby a given 

 suit was connected with a pile having a given location 

 on the table. In the second pack the order of the 

 cards was of course different ; the suits on the table 

 were therefore differently located, and the memories of 

 the first associations still persisting, they directly inter- 

 fered with the second performance, causing false move- 

 ments, and so increasing the time. The demonstration 

 here of the loss of energy in learning what needs only 

 to be unlearned is very striking, and if one experience 

 produces such an effect it is not difficult to understand 

 how habits early formed and long cultivated become so 

 difficult of eradication. With habits come rhythms in 

 activity, and, recognising the importance of rhythms of 

 this nature, the training may be adjusted to them, thus 

 catching the system at the most favourable moments. 



., 1893. 



