IV. TESTS OF LEARNING ABILITY 



(a) THE MAZE TEST 



IN the maze test, the mice were first given an initial learning test 

 of seventeen trials. This was a desirable number for two reasons; 

 first, because it was sufficient for the average mouse to learn the maze, 

 and secondly, because the seventeen trials could be divided into three 

 groups representing comparatively distinct stages in the course of 

 learning. The first stage includes the first two trials which are 

 largely affected by chance, and although given here for complete- 

 ness, are not averaged in the final ratings for each individual. The 

 second group, including the next five trials, represents a period of 

 continued rapid, but less variable learning; the third group, includ- 

 ing the following ten trials, covers the period of slow or nearly com- 

 pleted learning. The first group of 90 mice was given only this 

 initial learning test of seventeen trials. The behavior of the latter 

 group of 93 mice was more completely studied. After the seventeen 

 trials the gates were changed, so that the ones that had been open 

 were locked, and those closed were open. This was an interference 

 test designed to give a measure of the adaptability of the animals. 

 It was necessary for the mouse to break the old habit, and learn to 

 get through the maze by way of the previously closed gates. In the 

 first trial after this change, the interference effects were pronounced, 

 although in the eleven subsequent trials the mice rapidly learned the 

 new order. The interference test was divided into two groups. The 

 first two trials were put in one group, and the remaining ten trials 

 in a second group. The first group of two trials gives a measure of 

 the direct effect of the interference upon the animal 's behavior, while 

 the second group of ten trials shows the degree to which this inter- 

 ference is carried over into the following trials, and, in a fashion, 

 indicates the adaptability of each animal and the flexibility of its 

 behavior. 



(b) THE MULTIPLE CHOICE TEST 



Upon finishing the interference tests the mice were immediately 

 started upon a second experiment which will be here called the mul- 

 tiple choice test. A plan of the apparatus is given in Fig. 2. The 

 mouse was placed in the maze, through the door marked "E," within 

 the first compartment. Here it had a choice of one of four gates, 



