Brains reasonably may be considered to be information processing systems, which acquire, store, and manipulate information in the service of adaptive behavior. Accordingly, learning and memory (i.e., acquisition and storage, respectively) are critical and central topics in neurobiology. A greatly increasing volume of research on learning and memory is a significant characteristic of current biological and behavioral approaches. There is ample reason to believe that this trend will continue because of the many advances that have emerged from recent studies relating learning and memory to their neural substrates, on the one hand, and placing them within their evolutionary and ecological contexts, on the other hand.