Numerous studies have proven the biological basis of memory formation and have begun to identify the biochemical traces and cellular circuits that are formed by experience, and which participate in the storage of information in the brain, its retention for long durations, and its retrieval upon demand. Cells in the nervous system have the capability of undergoing extremely long-lasting alterations in response to hormonal, pharmacological, and environmental stimulations. The mechanisms underlying this neuronal plasticity are activated by experiential inputs and operate in the process of learning and the formation of memories in the brain. This volume presents research areas which have not been highlighted in the past. In addition to studies on the involvement of functional proteins in neuronal adaptation, this volume presents developments on the critical roles of bioactive lipids and nucleotides in these processes.