Stimulus equivalence and the untrained acquisition of stimulus functions

There is a rapidly growing area of research under the general heading of stimulus equivalence that has important implications for understanding some very basic and important issues in the fields of learning and cognition. These include the untrained acquisition of novel stimulus functions, symbolic behavior, the development of concepts or categories, and the development and behavioral effects of beliefs, expectancies, and schema. This research also has implications for understanding the development and treatment of several clinical disorders including substance abuse, anxiety disorders, and depression. The present paper describes the basic stimulus equivalence phenomena and reports several laboratory-based studies that explore its clinical implications. It concludes with a brief description of the general implications of this research.