Original Research ARTICLE
Role played by the passage of time in reversal learning
- 1School of Psychology, University of New South Wales, Australia
- 2School of Psychology, University of New South Wales, Australia
Reversal learning is thought to involve an extinction-like process that inhibits the expression of the initial learning. However, behavioral evidence for this inhibition remains difficult to interpret as various procedures have been employed to study reversal learning. Here, we used a discrimination task in rats to examine whether the inhibition produced by reversal learning is as sensitive to the passage of time as the inhibition produced by extinction. Experiment 1 showed that when tested immediately after reversal training, rats were able to use the reversed contingencies to solve the discrimination task in an outcome-specific manner. This ability to use outcome-specific information was lost when a delay was inserted between reversal training and test. However, interpretation of these data was made difficult by a potential floor effect. This concern was addressed in Experiment 2 in which it was confirmed that the passage of time impaired the ability of the rats to use the reversed contingencies in an outcome-specific manner to solve the task. Further, it revealed that the delay between initial learning and test was not responsible for this impairment. Additional work demonstrated that solving the discrimination task was unaffected by Pavlovian extinction but that the discriminative stimuli were able to block conditioning to a novel stimulus, suggesting that Pavlovian processes were likely to contribute to solving the discrimination. We therefore concluded that the expression of reversal and extinction learning do share the same sensitivity to the effect of time. However, this sensitivity was most obvious when we assessed outcome-specific information following reversal learning. This suggests that the processes involved in reversal learning are somehow distinct from those underlying extinction learning, as the latter has usually been found to leave outcome-specific information relatively intact. Thus, the present study reveals that a better understanding of the mechanisms supporting reversal training requires assessing the impact that this training exerts on the content of learning rather than performance per se.
Keywords: Reversal Learning, Extinction learning, Inhibition (Psychology), spontaneous recovery, Pavlovian conditioning, instrumental conditioning, Discrimination Learning
Received: 18 Oct 2017;
Accepted: 05 Apr 2018.
Edited by:Martin Giurfa, UMR5169 Centre de Recherches sur la Cognition Animale (CRCA), France
Reviewed by:Aaron P. Blaisdell, University of California, Los Angeles, United States
John T. Green, University of Vermont, United States
Copyright: © 2018 Goarin, Lingawi and Laurent. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Vincent Laurent, University of New South Wales, School of Psychology, Sydney, 2052, Australia, firstname.lastname@example.org