From salt navigation in Caenorhabditis elegans to robot navigation in urban environments, or: the role of sensory computation in balancing exploration and exploitation during animal search

Effective spatial navigation is essential for the survival of animals. Navigation, or the search for favorable conditions, is fundamentally an adaptive behavior that can depend on the changing environment, the animal's past history of success and failure and its internal state. C. elegans implements combinations of systematic and stochastic navigational strategies that are modulated by plasticity across a range of time scales. Here, we combine experiments and computational modeling to characterise adaptation in gustatory and nociceptive salt sensing neurons and construct a simulation framework in which animals can navigate a virtual environment. Our model, and simulations on a variety of smooth, rugged or complex landscapes, suggest that these different forms of sensory adaptation combine to dynamically modulate navigational strategies, giving rise to effective exploration and navigation of the environment. Inspired by this compact and elegant sensory circuit, we present a robotic simulation framework, capable of robustly searching for landmarks in a toy simulation environment.