Comparative Cognition, Hippocampal Function, and Recollection

What is conscious recollection? Is it special to humans or do animals have this capacity as well? What brain circuitry supports the kinds of information processing that constitute recollection? This review will outline recent evidence from studies on rodents, monkeys and humans bearing on these questions. This review focuses on a comparative approach that identified features of recollection that can be studied across species, explores these elements of recollection in animals, and examines in animals the role of the medial temporal areas that are critically involved in conscious recollection in humans. Substantial evidence indicates that animals exhibit all the fundamental features of recollection, that these abilities depend on the hippocampus in animals as well as humans, and that neuronal representations in the hippocampus reflect information processing fundamental to the features of recollection. In addition, the functional circuitry of the hippocampal system is largely conserved across species, and its organization suggests information processing mechanisms that support the features of recollection are common across species.