Invertebrate learning and memory: From behavior to molecules

The purpose of this review is to survey recent progress made in the study of learning and memory in vertebrate animals. For reasons of both focus and constraints on length, we restrict the scope of the review in two ways. First, because of the recent major advances in the area, we primarily consider only instances of associative learning in invertebrates. Second, because the central theme of the review centers on neuronal mechanisms of learning, we only consider preparations in which some form of cellular or molecular analysis has been carried out, or is at least quite feasible. We divide the review into three parts. We first provide a brief overview of the major psychological principles and paradigms used in the modern study of learning and memory. We then consider how these principles and paradigms have been applied in a variety of invertebrate animals. We conclude with an attempt to synthesize some of the common themes and convergent ideas that have emerged from the study of learning and memory in invertebrates.