EFFECTS OF STRYCHNINE UPON RATE OF LEARNING 167 



a saving in the amount of practice necessary for learning. Caf- 

 feine in large doses markedly increases the amount of practice 

 consumed in learning and the retardation of the rate of learn- 

 ing seems proportional to the amount of the drug administered. 



During training the animals under the influence of strychnine 

 move more slowly, and those under caffeine more rapidly than 

 normal animals. Associated with these effects are a seeming 

 caution in approaching the turns of the maze appearing in the 

 strychninized animals and an exaggerated carelessness in those 

 under caffeine. These effects largely disappear when the habits 

 have become automatized. After the habit has been perfected 

 strychnine increases and caffeine diminishes the accuracy of the 

 animals' performance. 



The results are complex and seemingly at variance with the 

 similarity of action accredited to the drugs by pharmacologists, 

 and, in view of our elementary knowledge of their effects upon 

 various sense organs and upon the autonomic nervous system it 

 is not possible to make any definite conjecture as to the way in 

 which the drugs bring about their effects upon the learning 

 process. 



The most confusing point is the direct opposition of the ef- 

 fects of caffeine and strychnine. Until further data is accumu- 

 lated upon the physiological action of these drugs it will not be 

 possible to apply the present data to the question of the relation 

 of inhibitory or excitatory nervous activity to learning. A 

 significant suggestion concerning the difference of action of the 

 drugs is given by Sajous ('12). He asserts that the first effects 

 observed after the administration of both drugs result from the 

 stimulation of suprarenal activity: Caffeine is more effective 

 than strychnine in producing this result and its effects are 

 almost wholly confined to this action: Strychnine, however, in 

 large doses soon attacks the spinal centers and its more pro- 

 nounced effects are due to its action on the central nervous 

 system. I have not been able to find the original data upon 

 which these statements are based and they are not in accord 

 with the more generally accepted accounts of the action of the 

 drugs, although there seems to be no conclusive evidence against 



