This chapter summarizes the literature on the anatomical and functional organization of the cuttlefish brain, with a focus on the structures involved in learning and memory processes (namely the vertical lobe system and optic lobes). Also, different learning paradigms that are commonly used in Sepia officinalis are described with, when possible, their neural correlates. Recent work on the early development of brain and memory is also reviewed. Some research directions to follow in the field of neurobiology of learning and memory in cuttlefish are suggested to better understand the extraordinary behavioral plasticity of these sophisticated invertebrates.

Understanding how memories are induced and maintained is one of the major outstanding questions in modern neuroscience. This is difficult to address in the mammalian brain due to its enormous complexity, and invertebrates offer major advantages for learning and memory studies because of their relative simplicity. Many important discoveries made in invertebrates have been found to be generally applicable to higher organisms, and the overarching theme of the proposed will be to integrate information from different levels of neural organization to help generate a complete account of learning and memory. Edited by two leaders in the field, Invertebrate Learning and Memory will offer a current and comprehensive review, with chapters authored by experts in each topic. The volume will take a multidisciplinary approach, exploring behavioral, cellular, genetic, molecular, and computational investigations of memory. Coverage will include comparative cognition at the behavioral and mechanistic level, developments in concepts and methodologies that will underlie future advancements, and mechanistic examples from the most important vertebrate systems (nematodes, molluscs, and insects). Neuroscience researchers and graduate students with an interest in the neural control of cognitive behavior will benefit, as will as will those in the field of invertebrate learning. - Presents an overview of invertebrate studies at the molecular / cellular / neural levels and correlates findings to mammalian behavioral investigations - Linking multidisciplinary approaches allows for full understanding of how molecular changes in neurons and circuits underpin behavioral plasticity - Edited work with chapters authored by leaders in the field around the globe – the broadest, most expert coverage available - Comprehensive coverage synthesizes widely dispersed research, serving as one-stop shopping for comparative learning and memory researchers

Individual recognition is often considered a cognitively challenging form of recognition because it requires flexible learning and memory. Because Polistes paper wasps are one of the few invertebrates known to have individual recognition, they provide a good model for exploring how individual recognition shapes cognitive evolution. Here, we review previous work on individual recognition in paper wasps with a particular focus on learning and memory. In this review, we (1) explore the evolution of individual recognition in paper wasps, including the selective pressures thought to shape the origin and maintenance of individual recognition; (2) discuss the extent of memory for specific individuals during paper wasp social interactions; (3) describe a negative reinforcement training method that can be used for comparative learning research in wasps and other invertebrates; and (4) explain how individual recognition has shaped the evolution of specialized visual learning in paper wasps.

The behavioral phenomenon of extinction resembles the decrease of a conditioned behavior when animals experience the presentation of a previously reinforced stimulus. In honeybees, extinction is studied in an appetitive learning paradigm, the olfactory conditioning of the proboscis extension response. Here, I describe recent work on extinction in honeybees (Apis mellifera) and its underlying molecular mechanisms. I demonstrate that extinction in honeybees shares behavioral and molecular similarities with extinction in vertebrates, and I discuss whether these similarities might indicate that extinction is a phylogenetically old mechanism.

A robot that senses and interacts autonomously with the real world can be used to embody specific hypotheses about the mechanisms of learning in invertebrates. Several models of olfactory learning circuits in the mushroom body of flies have been proposed. To use this to control a robot, it is crucial to understand not only when and how changes in synaptic strength occur but also how those synaptic changes fit within a circuit that produces ongoing behavior. Considering this problem from a robotic perspective reveals some conflicting assumptions made in current research that need to be resolved.

The marine snail Aplysia californica exhibits a simple defensive withdrawal reflex that can undergo several forms of learning. In particular, the reflex can exhibit long-term sensitization (LTS), a form of nonassociative memory. LTS is mediated by long-term facilitation (LTF) of the monosynaptic connection between the sensory and motor neurons that mediate the withdrawal reflex. LTS and LTF represent one of the best understood model systems of long-term memory extent. Furthermore, discoveries from work on this system have provided fundamental insights into the cellular and molecular mechanisms that mediate the induction and maintenance of long-term memory. This chapter reviews this work; it concludes with a discussion of recent studies of the role of protein kinase M in the persistence of the long-term memory and of memory reconsolidation in Aplysia. It is suggested that the study of LTS and LTF can provide important mechanistic information on these two intriguing memory phenomena.