Drugs affecting the nerves and the brain are among the most commonly used in contemporary medicine. This study examines the mechanisms by which such substances cause their therapeutic or undesirable side-effects in relation to underlying processes and pathological phenomena. The book fills the information gap between large textbooks and highly specialized reviews and monographs. Mechanisms of drug actions are examined mainly at the cellular and subcellular levels. Molecular, neurochemical and electrophysiological approaches are used in an attempt to provide a rational study of drugs acting on the nervous system.