Learning, extinction, and relearning of running and basal skin resistance (BRL) in a segmented straight alley

Abstract

A test was devised of the interpretation of the goal gradient found by Di Lollo and Walker (1964) in terms of the handling of the animal rather than in terms of rg. Two groups of 12 animals each were run in the same maze with a starting box attached. During a five min. delay period in the starting box, one group was handled during the entire 2nd min. and the other group during the 4th min. On each trial animals were retained in each of the six segments of the maze for one full minute before the gate was raised giving access to the next segment. Two trials per day were given, separated by 4 hours. There were 10 reinforced learning trials, 8 trials of extinction, and 4 trials of relearning. Handling produced a drop in BRL during the 5 min. delay period. BRL rose during learning, dropped during extinction, rose again during relearning. There was no evidence of a goal gradient in either mean or individual day data. The findings constitute additional evidence that the goal gradient may be attributable to the manner in which the animal is handled while being placed in and removed from the maze.