ABSTRACT
The experience of a reward appears to enhance memory for recent prior events, adaptively making that information more available to guide future decision-making. Here, we tested whether reward enhances memory for associative item-location information and also whether the effect of reward spreads to other categorically-related but unrewarded items. Participants earned either points (Experiment 1) or money (Experiment 2) through a time-estimation reward task, during which stimuli-location pairings around a 2D-ring were shown followed by either high-value or low-value rewards. All stimuli were then tested for location memory or recognition (yes/no), immediately and after a 24-hour delay. Across both experiments (combined analysis), there was a robust improvement in location memory following high-value rewards, even though evidence supporting this effect was reliable in Experiment 2 but not in Experiment 1. The memory-enhancing effect of reward was observed on both the immediate and delayed location-memory tests. Reward-enhanced memory for both directly rewarded stimuli and categorically related stimuli that were not directly rewarded. No reliable effect of reward value on yes/no recognition-memory performance was observed in either experiment. We hypothesise that reward enhances the consolidation of recent experience and conceptually related memories to make these more available for future decisions.
Acknowledgements
The authors thank Y. Catherine Han for her feedback on the statistical analyses and for creating the avatar images used in Experiment 1, and Caelie P. McRobert and Thomas C. Dixon for their support with data collection for both experiments.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Data availability statement
The data and materials for all experiments are available at the Open Science Framework, https://osf.io/zv4ah/. None of the experiments were pre-registered in advance, although the two experiments are largely replications of each other.
Correction Statement
This article has been corrected with minor changes. These changes do not impact the academic content of the article.