Resurgence: the role of extinction

Three hens were trained to door push and three were trained to head bob usi ng food as the reinforcer (Behaviour training). A period of extinction foll owed. Each hen was then trained to perform the other behaviour (Behaviour 2 ) and this was followed by seven sessions of extinction. This whole sequenc e was repeated six times. with two sessions of extinction following Behavio ur 1 training. Over the repeated extinction conditions there were decreases in responding early in extinction, for both Behaviours 1 and 2, compared w ith the first condition. Behaviour in the later extinction sessions could b e studied for Behaviour 2 only, and it was found to increase relative to th e first condition, over repeated extinction conditions. The occurrence of B ehaviour 1 during the extinction following the training of Behaviour 2, tha t is the resurgence of Behaviour 1, both over the whole of and in the first session of each extinction phase, was variable and tended to increase over these six conditions. Thus it is possible to study resurgence using a with in-subject design but the effect of repeated extinction conditions needs to be considered. The period of extinction immediately following Behaviour 1 training was then increased to nine sessions for two replications of the wh ole sequence. This was followed by two repents of the sequence with no sess ions of this extinction and then by another repeat, with nine sessions of t his extinction phase. over these five conditions the total resurgence of Be haviour 1 was generally greater when there were no sessions of extinction i mmediately following Behaviour 1 training, than when there were nine sessio ns. This result was more marked for the resurgence of Behaviour 1 in the fi rst session of the extinction of Behaviour 2. Thus, these data support the hypothesis that the resurgence of Behaviour 1 is the result of the preventi on of the extinction of Behaviour 1 by training Behaviour 2. At a similar p oint in extinction, the number of occurrences of Behaviour 1 in its own ext inction was not significantly different from the number of occurrences of B ehaviour I during the extinction of Behaviour 2. This fails to support the hypothesis that resurgence is induced by the extinction of Behaviour 2. (C) 2000 Elsevier Science B.V. All rights reserved.