Document Type


Digital Object Identifier (DOI)


Journal Title

International Journal of Comparative Psychology

Publication Date



The connection between reduced reinforcement probability and increased behavioral variability hasbeen well established in recent years (Gharib, Gade, & Roberts, 2004; Stahlman, Roberts, & Blaisdell, 2010). Researchers have hypothesized that this relationship is an adaptive one - it is beneficial for animals to increase behavioral variability in response to low likelihood of success,because this increase in variability potentially allows them to discover new behavioral options that are more highly rewarded. We conducted a study to investigate the relationship between behavioral variability and reward probability in an ecologically valid experimental task. We trained rats to search for hidden food in the presence of either of two landmarks, each that signaled a different likelihood of reward (i.e., HI and LO). Variation in locations searched was higher in the presence of the LO probability landmark. These results build on prior findings that reward expectation drives behavioral variability.


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Publisher Statement

The International Journal of Comparative Psychology is sponsored by the International Society for Comparative Psychology. It is a peer-reviewed open-access digital journal that publishes studies on the evolution and development of behavior in all animal species.