The use of classical conditioning in planaria to investigate a non-neuronal memory mechanism

The concepts of learning and memory have fascinated man since before the advent of science. The evolutionary significance of these mechanisms is clear. If an organism is able to learn and remember information about its environment, it will have a distinct advantage in survival. Biologically, learning is described as the inherent process in which an organism senses an environmental stimulus and undergoes adaptive changes in behavior as a response. Psychologists study learning in laboratories using simple organisms as model systems for humans, and observe specific behavioral changes which indicate the occurrence of learning. As of yet, the complete physiological mechanism of learning is unknown, and so the behavioral approach to learning research is the most commonly accepted. In this study, the planarian is used as the model organism in an investigation of the nature and location of the memory mechanism. Classical conditioning is utilized to train the organism, and the regeneration process is used to research the physiological aspects of the memory mechanism. Ultimately, an understanding of this mechanism in the planarian may hold implications for an understanding of learning and memory in higher organisms, such as humans.