Social observation enhances cross-environment activation of hippocampal place cell patterns

TLDR

Humans and animals learn by observing others, and the local enhancement theory suggests that social presence in an environment aids others’ spatial understanding. The study aimed to investigate the neural basis of local enhancement by recording hippocampal place cells in rats during observation and self‑running. Place cells were recorded in rats in a box while a demonstrator ran on a nearby track, and again while the rats ran on the track themselves. Place cell sequences during self‑running were also activated in the box, even before the rats ran on the track and only when a demonstrator was present, indicating that social observation can prime spatial representations without exploration and may underlie local enhancement.

Abstract

Humans and animals frequently learn through observing or interacting with others. The local enhancement theory proposes that presence of social subjects in an environment facilitates other subjects' understanding of the environment. To explore the neural basis of this theory, we examined hippocampal place cells, which represent spatial information, in rats as they stayed in a small box while a demonstrator rat running on a separate, nearby linear track, and as they ran on the same track themselves. We found that place cell firing sequences during self-running on the track also appeared in the box. This cross-environment activation occurred even prior to any self-running experience on the track and was absent without a demonstrator. Our data thus suggest that social observation can facilitate the observer's spatial representation of an environment without actual self-exploration. This finding may contribute to neural mechanisms of local enhancement.