The curious interpretation of novel object recognition tests

Novel object recognition tasks are commonly used to assess memory in rodents. These tests rely on an innate preference for exploring objects that are new or have been moved or changed. However, this preference, while normally seen in control conditions, is not immutable. Stressful experiences as well as lesions and genetic mutations can lead mice and rats to show clear preferences for exploring familiar objects and familiar locations. This opinion article discusses the evidence for changes in novelty preference, implications of this lability for assessing memory, and the significance of shifts in novelty preference as a readout of changes in curiosity with implications in approach-avoidance behavior and explore-exploit decision-making. Finally, we provide some recommendations for reporting and interpreting novelty preference task findings moving forward.