Rather than being coupled to absolute coordinates, such as magnetic north, direction is represented in the brain as the relative orientation of an animal in its current environment, termed “heading”.
Similar content being viewed by othersĪ sense of direction is essential for animals to accurately perceive and move through their environment. Our results suggest an RSC circuit for anchoring heading representations to environmental visual landmarks. Finally, decoding analyses reveal unique contributions to heading from each class. While some functional classes mirror RSC inputs, a newly discovered class coregisters visual and thalamic signals. Next, we found that RSC receives functionally distinct projections from visual and thalamic areas and contains several functional classes of neurons. We show that RSC neurons are tuned to the animal’s relative orientation in the environment, even in the absence of head movement. To investigate how population-level heading responses are aligned to visual input, we recorded from retrosplenial cortex (RSC) of head-fixed mice in a moving environment using two-photon calcium imaging. Head direction cells in distributed brain regions receive a range of sensory inputs, but visual input is particularly important for aligning their responses to environmental landmarks. Spatial cognition depends on an accurate representation of orientation within an environment.
