The Hex-Maze: A previous knowledge task for mice

New information is rarely learned in isolation, instead most of what we experience can be incorporated into previous knowledge networks. However, most rodent laboratory tasks assume the animal to be naive with no previous experience influencing the results, which may be a factor contributing to the current crisis of translational failure when going from the basic lab to human research. Previous research in rats has indicated, that previous knowledge in form of a schema can facilitate knowledge acquisition and accelerate systems consolidation: memories become more rapidly hippocampal independent and instead rely on the prefrontal cortex. These results emphasized the need for more tasks that investigate previous knowledge effects and can be applied in both rats and mice. Here, we developed a new spatial navigation task, training food locations in a large, gang-way maze the Hex Maze. Analysing both with and across session performance, we can show simple memory effects as well as multiple effects of previous knowledge accelerating both online learning as well as performance increases during offline periods. These effects are reminiscent of both Learning-Set and Schema, two different previous knowledge effects described previously in the literature.