Conjunctive Representation of Position, Direction, and Velocity in Entorhinal Cortex

TLDR

Grid cells in the medial entorhinal cortex are part of an environment‑independent spatial coordinate system that may be updated during self‑motion‑based navigation by integrating positional, directional, and translational information. The study aimed to determine how location, direction, and distance information are integrated in the grid‑cell network. The authors recorded from each principal cell layer of MEC in rats exploring two‑dimensional environments. Layer II is dominated by grid cells, whereas deeper layers contain grid cells co‑localized with head‑direction cells and conjunctive grid‑by‑head‑direction cells, and all cell types are modulated by running speed.

Abstract

Grid cells in the medial entorhinal cortex (MEC) are part of an environment-independent spatial coordinate system. To determine how information about location, direction, and distance is integrated in the grid-cell network, we recorded from each principal cell layer of MEC in rats that explored two-dimensional environments. Whereas layer II was predominated by grid cells, grid cells colocalized with head-direction cells and conjunctive grid x head-direction cells in the deeper layers. All cell types were modulated by running speed. The conjunction of positional, directional, and translational information in a single MEC cell type may enable grid coordinates to be updated during self-motion-based navigation.