This chapter focuses on the neural substrate of mental representation and cognitive maps. In 1948, American psychologist Edward Chance Tolman postulated that spatial learning requires a representation of the environment in which a subject evolves. This concept has been popularized under the term ‘cognitive map’. These maps would retain information about the spatial relationships between different places, which supposes the existence of a coordinate system, or referential. The chapter then considers the role of the hippocampus in memory processes. According to psychologists, there are two types of memory: declarative and procedural. Procedural memory describes the ability to reproduce learned behaviour. On the other hand, declarative memory is based on very different processes. Whatever form it takes, it undoubtedly requires the construction of a mental representation. This mental representation is likened to the cognitive maps theorized by Tolman.