Emulation as a behavioral strategy underlying spatial observational learning in rats

Humans and several non-human species have shown the ability to learn by observing an experimented conspecific. A basic form of this learning is spatial observational learning (sOL), where a naïve animal improves their accuracy in a spatial task after witnessing a demonstrator solve the same task. This ability has gained neurophysiological support with the discovery of hippocampal CA1 social place cells, which encoded the position of others, and the role of CA2 and ventral CA1 neurons in processing and storing social memory. However, the direct role of the hippocampus in accomplishing sOL and the behavioral changes adopted by the observer animal have not been fully understood. Observational learning can be explained by behavioral processes such as imitation, emulation, or local enhancement. We used a modified version of the oasis maze to unravel the strategy unfolded by naïve observer rats during sOL. Our results suggest that emulation is the primary strategy implemented by observers by switching from a free-foraging approach to goal-directed behavior. Furthermore, the pharmacological inactivation of the hippocampus during the observation period impeded sOL, revealing the necessity of this structure for engaging in this behavioral change. Our results propose that the hippocampus is necessary for the internal representation of the demonstrator in the space and their movement towards a particular area and for the animal comprehension of the behavioral purpose of others during observational learning.