5 - Discrimination learning and prediscrimination effects

Summary

In this chapter, we will review the application of frustration theory to the explanation of another case of reward–nonreward intermittency – discrimination learning. We will consider the role of frustrative factors of arousal and suppression in the formation of discriminations, and the mediating action of anticipatory frustration and counterconditioning in the retardation and facilitation of discrimination learning. The discrimination learning we will consider involves separate experiences with or exposures to the discriminanda, which first the case of dispositional learning. We should therefore briefly review the history of the involvement of frustration in such “go/no-go” discriminations.

Frustrative factors in discrimination learning

The Hullian analysis of instrumental discrimination learning (Hull, 1950, 1952), which has been and continues to be influential, did not include an active, frustrative role for nonreinforcement. In broad outline, while Hull did maintain that the primary process involved was differential reinforcement, he held that its major function was (a) to neutralize the effect of the background or context stimuli that occur in the presence of both discriminanda, (b) to increase the power of the positive stimulus to evoke the (approach) response, and (c) to decrease the power of the negative stimulus to evoke that response. However, in Hull's theorizing the negative stimulus did not elicit avoidance of nonreward; rather, responses elicited by the S – permitted accumulation of an inhibitory state, reactive inhibition (I_R), which, not offset by the growth of excitatory strength and particularly under massed-trial conditions, led to the extinction of responding to S –.