RELATIVE DISTANCE AS A FACTOR IN THE WHITE 



RAT'S SELECTION OF A PATH 

 \ 



J. E. DE CAMP 



The Pennsylvania State College 



Elimination of errors and decrease in length of path from 

 starting point to goal (usually food) are characteristic of animal 

 learning. Of two paths leading to food, one being longer, the 

 animal soon chooses the shorter. This has been observed with 

 white rats in their learning of mazes. This article is a report 

 of an attempt to study this selection by the white rat of the 

 shorter of two paths. 1 



Two mazes, one rectangular and one circular, were used. The 

 rectangular maze will be referred to as maze A; the circular, 

 as maze B. Maze A (see diagram 1) was constructed of 12-inch 

 redwood boards placed edgewise on the floor. Dimensions of 

 maze A, 14.2 by 7.2 feet, outside measurement. Width of path, 

 1 foot. There were two food-boxes, Fi and F 2 , and one starting 

 box, H . The starting box was fixed at the center of one of the 

 shorter sides, and the rat was admitted into the maze by means 

 of a sliding door and string. The maze was covered with gal- 

 vanized wire mesh. Length of entire path, 38.8 feet. Maze B 

 (see diagram 2) was circular. Diameter, outside to outside, 

 6 feet. Path, 6 inches wide and 34.6 feet long. The walls 

 were made of black cardboard strips fastened to the floor. Height 

 of walls, 8 inches. Starting box H, fixed. Food-boxes, FI and 

 F 2 , were adjustable for different distances from H. S, Fi, and 

 F 2 all had doors controlled by strings from the observer's station. 



The method was the same for both mazes. One of the food- 

 boxes was provided with food and placed at a certain distance 



1 The experimental work reported in this article was done in the psychological 

 laboratory of Stanford University. Its incompleteness is apparent. The 

 writer's transfer from Stanford to Pennsylvania State College occurred before 

 the work could be completed. 



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PSTCHOBIOLOGY, VOL. II, NO. 3 



