A modular gate system for autonomous control of rodent behavior

Rodent mazes have been used for decades to study the neural basis of behavior. Advancements in rapid prototyping techniques and access to affordable electronics allows laboratories with sufficient expertise in engineering and programming to customize and construct maze apparatuses and behavioral tasks, thereby increasing the ability of their studies to answer specific scientific questions. We designed and built a rodent gate system that lowers this bar of expertise even further. The NC4gate system is a robust mechanical design that can be built using low-cost hardware and execute thousands of cycles before maintenance. Up to 512 gates can be controlled using a single computer. Users can control the gates interactively using a Python-based graphical interface and programmatically using an extensible API. We hope that the open-source hardware / software and extensive documentation enables laboratories to build these affordable and robust gates and seamlessly incorporate automatic behavior control into their existing or new rodent tasks. Significance StatementRodent mazes are used by thousands of laboratories and research institutions across the world to study learning and memory, as well as the effects of pharmacological, genetic and environmental manipulations. Ideally, maze and task designs should be customized to the scientific questions at hand. It is challenging, however, for many laboratories to build, program, and operate custom mazes, requiring them instead to rely on expensive and proprietary commercial solutions. The most complex components of most mazes are moving gates that restrict and direct rodent behavior. Here we provide the open-source hardware and software for a gate system that is extensible, affordable and robust, removing this critical barrier to customized mazes.