The weakening of one Thorndikian response following the extinction of another.

Abstract

19 rats were divided into 4 groups. All rats were given forty rewarded trials on each of two different activities, one of which was depressing a horizontal bar, the other, pushing sideways a vertical bar. After training, all rats were given exptl. extinction by non-reinforcement first on one bar, and 5 mins. later, on the other bar. Training and extinction orders were balanced so that on each extinction all of the 4 possible training and extinction sequences were represented. Comparison of the mean responses during the two extinctions revealed a decrease of 63% from the 1st to the 2d. The difference between the value at the 1st extinction, 43, and that at the 2d, 16, was reliable, the Dif./Dif. being 423. Comparison of the means for the sub-groups suggests the possible presence of "positive generalization" and "interference" effects.