ABSTRACT
Questions about long-term potentiation (LTP) and memory are usually cast in terms of the biochemistry of storage. Are the ionic fluxes, enzymatic systems, and so forth involved in triggering LTP the actual processes whereby memory encoding occurs? Similarly, do the stable alterations in synapses that account for the remarkable persistence of LTP constitute the modifications that represent a memory trace? It need not be emphasized that answers to these questions are of profound importance and relate to the historic goals of research on learning and memory in animals. But LTP also raises, in a particularly cogent manner, subtle but farreaching questions about the relationship between specific neurobiological features and the many attributes of behavioral memory. Thus, LTP possesses a variety of characteristics, some of which can be projected onto one or another aspect of memory (for example, extreme persistence), as well as others which have no obvious correspondence with behavior (for example, the extent to which synaptic strength is increased by LTP). In addition, recent physiological experiments produced a set of rules that describe how various naturally occurring activity patterns interact with cellular chemistries to produce LTP (Larson & Lynch, 1986, 1988). If the potentiation effect is involved in memory, then these spatiotemporal relationships should be manifested in some aspect of behavior, but what this might be is completely unknown.
