The Rescorla-Wagner Model: what it is and how it explains learning

In 1972 Robert A. Rescorla, and Allan R. Wagner proposed a very relevant theoretical model for the psychology of learning. This is the Rescorla-Wagner model., based on classical conditioning and the concept of surpriseness.

Here we will know the characteristics of this model and what it intends to explain.

• Related article: "Classical conditioning and its most important experiments"

Rescorla-Wagner model: characteristics

The Rescorla-Wagner Model was expounded in 1969 at a series of classical conditioning conferences in Canada. It is the most influential theory of classical conditioning, and the one that has generated the most amount of research.

The authors initially They gave it the name Variations in the effectiveness of reinforcement and non-reinforcement., but later it was recognized as the Rescorla-Wagner Model (1972).

The model is based on classical or Pavlovian conditioning, beyond the associative learning of contingent stimuli. The objective of the Rescorla-Wagner Model is predict and describe changes (trial by trial) of associative strength

that unites a stimulus (or more) conditioned with the unconditioned stimulus.

The central idea of ​​the model is the competition that occurs between various stimuli for associating with the unconditioned stimulus. In addition, it highlights other concepts that we will see below.

The associative force

The model considers conditioning as a variation in the associative force that relates conditioned stimuli to unconditioned ones. The essential parameters are their respective intensities or their "salience" (central concept of the model).

This associative force is an intervening or intermediary variable, which integrates stimuli and responses. It is inferred mathematically through the measurement of the conditioned response.

On the other hand, the associative strength is limited (values ​​from 0 to 100). Once an IS is no longer surprising because it is already predicted by a CI with 100% certainty (force associative value of 100), there is no need to continue learning, not even to predict it with another CI.

• You may be interested in: "History of Psychology: authors and main theories"

surpriseness of the unconditioned stimulus

Depending on the model, conditioning or learning will occur when the unconditioned stimulus (US) is unexpected (IS surpriseness). That is, the animal learns about a CS when the US is unexpected.

In this way, if the US is surprising, the animal will pay attention to the conditioned stimuli that precede it, that is, it will learn to be able to predict better in a future that the IS approaches, from the ECs. According to Rescorla and Wagner, this learning is a tremendously useful ability for survival in the animals.

Instead, if the IS is not unexpected (does not cause surprise), it will not be possible to continue learning.

If we relate surprise to the associative force already mentioned, we know that the more surprising an IE that appears after the CS, that CS has less associative force with that IS (because if it surprises us, it is because we expected that it would not appear the IS). In other words, the IS gives the associative strength to the CS as a function of surpriseness.

How does learning occur?

Thus, as we have seen, classical conditioning occurs as a consequence of the quantitative variations in the associative strength between conditioned (ECs) and unconditioned (IS) stimuli.

The variations depend on a positive or negative discrepancy between the associative strength that the organism at a given moment and the true association that occurs in the environment between the ECs and the IEs.

These variations consist of changes that the larger they are, the more conditioning or learning they will produce.

Later model: Mackintosh's theory

The first theory to emerge as a competency of the Rescorla-Wagner model was Mackintosh's theory of attention (1975). This theory does not suppose that learning depends on the discrepancy of the associative strength between a conditioned stimulus with respect to a constant value of the unconditioned stimulus.

Instead, he posits that the value of the conditioned stimulus is not constant to the organism but changes through experience.

Mackintosh's theory states that preexposure to a stimulus hinders its subsequent conditioning (the appearance of the conditioned response). That is, if the animals are exposed to a CS before conditioning with the US, they end up "interpreting" that this CS is irrelevant.

Mackintosh also suggested that animals try to get information in the environment that allows them to predict the occurrence of biologically relevant events (EI's).

Bibliographic references:

• Perez-Acosta, A. (2001). The Rescorla model: Wagner at twenty. Theory and fundamentals. Psicologiacientífica.com magazine
• Pérez-Acosta, A, Rozo, J. and Baker, H. (2003). Milestones of the molar perspective of classical conditioning. Psychology from the Caribbean, 12, 2-12.