A navigational system for investigating multi-sensory integration in Caenorhabditis elegans

Animals use different sensory cues to guide their behaviors. How a nervous system performs multi-sensory integration remains an open question in neuroscience. Here, we study how the nematode Caenorhabditis elegans integrates temperature and salt stimuli, two environmental cues that are essential for survival. We report the development of a navigational system that allows stable, linear, and orthogonal temperature gradient and salt gradient to be simultaneously presented to an animal. By combining this setup with a tracking and calcium imaging system, we analyze the behavioral strategies of C. elegans and investigate the functions of two cilia sensory neurons—AFD and ASER—that attend the behavior. Our work opens a new window into interrogating the neural mechanisms for multi-sensory integration in a compact nervous system.