A theory of Pavlovian conditioning : Variations in the effectiveness of reinforcement and nonreinforcement

In several recent papers (Rescorla, 1969; Wagner, 1969a, 1969b) we have entertained similar theories of Pavlovian conditioning. The separate statements have in [act differed more in the language of their expression than in their substance. The major intent of the present paper is to explicate a more precise version of the form of theory involved, and to indicate how it may be usefully applied to a variety of phenomena in· volving asso('iative learning. The impetus for a new theoretical model is not generally a new datum which dearly disconfirms existing theory. It is more likely to be the accumulation of a salient pattern of data, separate portions of which may be ade(luately handled by separate existing theories, but which apo pears to invite a more integrated theoretical account. Such, at least, is the better description of the background of the present work. In the sections which follow we will first describe certain data from our laboratories which exemplify the kind of observations which have encouraged the present theorizing. The theory will then be presented in sufficient detail to show how it may be applied to experimental situations involving a variety of Pavlovian conditioning arrangements. Finally, we will briefly discuss the theory in relationship to more conventional approaches.