9807476 Bingman A large body of research has established the crucial role of the hippocampus in learning and memory. In animals, the hippocampus is particularly important for learning about space. Of special interest are electrophysiological studies in rats that have demonstrated the existence of "place cells", cells that respond when an animal is in a particular location in its environment. It is generally believed that these place cells participate in the neural representation (map) of environmental space that enables animals to efficiently navigate among goal locations. Given the importance of this research for understanding brain/behavior relations, it is surprising that place cells have only been intensively studied in rats. But to what extent do the properties of place cells in rats generalize to other vertebrate species and to what extent are they a necessary design feature of hippocampal mediated spatial representations? The proposed research is designed to investigate the possible existence and eventual properties of cells in the bird hippocampus that display space specificity (i.e. place-like cells). Electrophysiological recordings of single units in the hippocampus will be taken from pigeons allowed to freely move in an open field environment. Unit activity data will then be correlated with simultaneously recorded location information from pigeons to determine if a unit responds preferentially when a pigeon is in a particular location. The data will then be used to determine whether rats and pigeons, species that have a hippocampus used for spatial learning but otherwise very different in terms of lifestyle, behavior and brain organization, represent space similarly at the neural level. The study could fundamentally change how we view the hippocampus and the spatial representations it constructs, the environmental/beha vioral features that control the activity of hippocampal cells, and the evolution of the relationship between brain and cognition.
