New methods for solving the Rescorla-Wagner model

Two new methods for generating predictions from the Rescorla-Wagner model are presented. One is to solve the simultaneous equations of the model as differential equations, and the other is to solve them as difference equations, by using recent computer software. The model has been described in terms of simultaneous difference equations, and its predictions have traditionally been derived by performing an iterative computer simulation. But the limit can be taken, and the model can be considered in terms of simultaneous differential equations. Computer software, such as Mathematica and Maple, can solve simultaneous differential or difference equations. The author shows how to use Mathematica for some experimental paradigms, from simple acquisition to more complex cue competition paradigms, and also explains the rule for constructing input. The relative merits of these methods and of simulation are discussed.