THE WHITE RAT AND THE MAZE PROBLEM 7 



1. Normal maze records — (a) rats trained; (b) rats untrained; 

 (c) discrimination experiment for (a) ; (d) discrimination experi- 

 ment for (b). 



2. Black-white maze records, true path black — (a) rats trained; 

 (b) rats untrained; (c) discrimination experiment for (a); (d) 

 discrimination experiment for (b). 



3. Black-white maze records, true path white — (a) rats 

 trained; (b) rats untrained; (c) discrimination experiment for 

 (a) ; (d) discrimination experiment for (b) . 



The reason for the use of the two pieces of apparatus was 

 this: After the first group of animals had learned the black 

 and white maze we wished to see whether it was really bright- 

 ness to which the animals were reacting. The other experiment 

 — the box with the black and white exits — was devised, there- 

 fore, to see whether the brightness experience carried over. 

 Then the suggestion arose that the differences which were seen 

 in the conduct of the rats might not be due to brightness alone 

 but that some of the changed results might be a general effect 

 of training. To meet this criticism not only were the experi- 

 ments doubled by the use of both maze and box, but groups 

 of animals trained upon the box afterward learned the maze 

 and animals trained upon the maze learned the box. In order 

 to make the normal group comparable the training also had to 

 be included in their case although the maze was uniform in 

 brightness. 



It may be objected that the contact values of the two media, 

 paper and cardboard, used in the first experiments differed and 

 that the air pressure, sound qualities, etc., were not the same 

 in the two paths. The work will have to face that criticism. 

 The training tests upon the problem box and the succeeding 

 experiments upon it seemed to show, however, that it was really 

 brightness to which the animals were reacting. The six blind 

 animals used upon the black-white maze furnished a further 

 control. If there were other sensory elements fused with vision 

 it does not affect the value of the experiment since this is nor- 

 mally true and since it was the visual element which was the 

 variable one. 



The tables submitted show only the time of a total reaction 

 and the errors. Leaving the true path, entering a cut de sac, 

 was counted as one error. Returns could not be counted as 

 errors since part of the maze was covered. For the same reason 



