International Series of Monographs in Cerebrovisceral and Behavioral Physiology and Conditioned Reflexes, Volume 3: Biology and Neurophysiology of the Conditioned Reflex and its Role in Adaptive Behavior focuses on the biological roots, characteristics, and nature of conditioned reflex and its function in adaptive behavior. The monograph first discusses the biological roots of the conditioned reflex. Concerns include sequential order of external influences and living protoplasm; anticipatory processes of protoplasm and the conditioned reflex; adaptive features of the conditioned reflex; and inborn signalization in higher animals. The book then takes a look at the nature of the unconditioned reflex, including biological nature of reinforcement; value of the temporal relationships of conditioned and unconditioned reflexes; and fixation of sequential order without the factor of reinforcement. The text describes systemogenesis as an evolutionary basis for the development of unconditioned reflexes; concepts concerning the nature of the coupling process; and hypothesis of the convergent coupling of the conditioned reflex. The book also examines functional system as a basis of the physiological architecture of behavioral acts. The monograph is a dependable source of data for readers interested in conditioned reflex and its function in adaptive behavior.