Theta sweeps accelerate cognitive map learning by broadcasting information to unvisited regions

Abstract

To support flexible behavior, animals need to learn map like representations of environments from limited experiences, but the underlying neural mechanisms remain unclear. Here, we propose that theta sweeps, a prominent feature in the activities of grid and place cells during active movement, can broadcast acquired sensory information to swept unvisited regions, accelerating cognitive map learning. To test this idea, we built a network of direction, grid, and place cell modules, in which theta modulation and firing rate adaptation generate theta sweeps, while Hebbian plasticity enables place cells to bind environmental observations. Simulations and ablations showed that the dorsal ventral grid organization produces multiscale, independent sweeps broadcasting acquired sensory information to a broad, fan shaped unvisited area, enabling unvisited regions to build place environment associations. The model further suggests that declining theta power as the environment becomes familiar acts as an annealing process, shifting from learning general information about the environment to making local refinements. The model makes three testable predictions: strong theta modulation accelerates early learning, environments with broader spatial correlations favor longer theta sweeps, and theta sweeps progressively shorten as environments become familiar. Together, our results support theta sweeps as a mechanism for accelerating cognitive map learning from limited explorations, and it sheds light on developing brain inspired algorithms for building world models.