A Computational Model for Latent Learning based on Hippocampal Replay

We show how hippocampal replay could explain latent learning, a phenomenon observed in animals where unrewarded pre-exposure to an environment, i.e. habituation, improves task learning rates once rewarded trials begin. We first describe a computational model for spatial navigation inspired by rat studies. The model exploits offline replay of trajectories previously learned by applying reinforcement learning. Then, to assess our hypothesis, the model is evaluated in a multiple T-maze environment where rats need to learn a path from the start of the maze to the goal. Simulation results support our hypothesis that pre-exposed or habituated rats learn the task significantly faster than non-pre-exposed rats. Results also show that this effect increases with the number of pre-exposed trials.