In path integration, animals use self-motion cues to judge their movement, enabling them to represent their location and orientation in an environment. Grid cells have been proposed to have a role in path integration, as these neurons exhibit spatially linked periodic firing fields. However, a direct link remains to be established between path integration and these firing patterns.

To examine this link, Peng, Throm et al. used a self-motion-based navigation task — the AutoPI homing task, conducted in the dark — to examine grid cell firing in mice navigating by path integration. In this task, a mouse navigated from a home base to an arena to find and press a randomly located lever. Pressing the lever released some food in the home base, so the animal then had to navigate (home) from the arena to the base to claim its reward.