Resistance to Extinction as a Function of Reinforcement Schedule and Training Level: A Test of Theios and Brelsford's Theory

Abstract

Two experiments were run in which one group of rats received 100% reward with 16 pellets per trial (100%-16), a second group received 50% reward with 16 pellets on rewarded trials (50%-16), and a third group got 50% reward with 32 pellets on rewarded trials (50%-32). From Theios and Brelsford's theory it was predicted that Group 50%-32 should show less resistance to extinction than Group 50%-16, since both were equated for habit strength but differed on incentive motivation. In Exp. 1 all groups had 32 acquisition trials whereas in Exp. 2 all groups had 64 acquisition trials. Aside from this difference the two experiments were identical. The partial reinforcement extinction effect occurred in both studies. In Exp. 1, Group 50%-32 did not show less resistance to extinction than Group 50%-16, however, in Exp. 2 this result was obtained and confirmed the prediction under test.