Context-specificity of target versus feature inhibition in a feature-negative discrimination.

Four experiments with rats examined the effects of a context switch on inhibition that was acquired during a feature-negative discrimination. A target conditioned stimulus was paired with food when it was presented alone but occurred without food when it was combined with a feature stimulus. A context switch following training did not disrupt inhibition conditioned to the feature. However, responding to the target was more difficult to inhibit when it was tested in a different context. It is suggested that both the target and the feature acquired inhibition and that the target's inhibition was especially sensitive to the context. The feature may inhibit responding to the target (a) by directly suppressing the representation of the food and (b) by activating the target's own inhibitory association with food, which is at least partly context-specific. Implications for theories of inhibition and negative occasion-setting are discussed.