No. 497] 



NOTES AND LITERATURE 



3. Removal of the long vibrissa? or "feelers" on the face at 

 first disturbed the rats greatly. But if, before testing them with 

 the maze, the rats were allowed forty-eight hours to become ac- 

 customed to the loss of the vibrissa?, then they threaded the maze 

 as readily as did normal rats. This was true even if these same 

 rats were blind or without smell. 



4. Altering the temperature conditions, changing the air cur- 

 rents in the maze, or making the feet insensitive does not disturb 

 the rats, so that the corresponding senses seem to play no part 

 in the behavior. 



5. The evidence is strong that taste plays no part in the 

 matter. 



Apparently then we can exclude sight, touch, smell, hearing, 

 taste and the temperature sense as factors of any importance in 

 finding the way through the labyrinth. How then does the 

 rat find its way ? 



Evidently the rat relies for its guidance mainly on the com- 

 plex of inner sensations due to its own movements, the amount 

 of effort it has put forth, and the like; the "kinesthetic and 

 organic sensations." In threading the maze, the animal learns 

 how much effort it is to put forth going in a certain direction, 

 which way and how much it is then to turn, how much effort to 

 put forth in the new direction, which way to turn again, etc. It 

 finally knows the entire path as a combination of such efforts and 

 turns. The behavior of the rat is somewhat like that of a person 

 who may, in the dark, walk about a house with which he is 

 familiar, threading his way among tables and chairs, without 

 touching them. But in man this involves many memory images 

 of the various objects and their relative positions and distances. 

 In the rat such images evidently play little if any part; it is 

 mainly a matter of amount of effort, direction of turn, and the 

 like. "Watson is inclined to conclude that the rat has no such 

 images; that the purely intraorganic sensations account for the 

 entire behavior; that the rat uses in threading the maze no sense 

 data from the outside, either past or present. 



If this is true, then if the trained rat could be started at the 

 entrance of the maze so as to get the proper "cue" at the 

 beginning, and then the entire maze lifted from the floor, so as 

 to leave a clear space to the food in the center, the rat ought 

 nevertheless to follow the same complex path that it follows when 

 the walls of the maze are present. "Would this occur? Could 

 not the experiment be tried? 



