Associative Relations in Instrumental Learning: The Eighteenth Bartlett Memorial Lecture

Instrumental learning involves three primary events: a stimulus (S), a response (R), and an outcome (O). Evidence is reviewed indicating the presence of binary associations among those events, as well as a hierarchical structure of the form S–(R–O). Experiments examining the conditions that produce learning, the content of the learning once it has occurred, and the way learning maps into performance all suggest the presence of such a hierarchical structure.