Neural correlates of visual object recognition in rats

Abstract

Invariant object recognition--the ability to recognize objects across size, rotation, or context--is fundamental for making sense of a dynamic visual world. Although initially believed to be unique to primates due to its complexity, emerging evidence suggests rodents, too, can recognize objects across a range of identity-preserving transformations. Here, we describe a comprehensive pipeline for investigating visual behavior in rats, from high-throughput training to cellular resolution imaging in awake, head-fixed animals. Using this suite of tools, we demonstrate that rats excel in visual object recognition and explore potential neural pathways which may support this capacity. We leverage our optical approach to systematically profile multiple visual areas with responses to a range of stimulus types recorded in the same neurons. Primary and higher-order areas of rat visual cortex exhibit a hierarchical organization consistent with a role in visual object recognition. However, marked deviations from the functional organization of primate visual cortex suggest species-specific differences in the neural circuits underlying visual object recognition. This work reinforces the notion that rats possess sophisticated visual abilities and offers the technical foundation for their use as a powerful model to link neuronal responses to perception and behavior.