ABSTRACT
Conditioned stimuli (CS) appear on either side of the front wall of a standard pigeon chamber, and the subject's position in relation to the keylight was monitored by a teeter-totter floor. Pigeons approach and peck the CS when it predicts an increased likelihood of food unconditioned stimuli (US) and withdraw from the same stimulus when it predicts a decreased likelihood of food US. This chapter focuses on analysis of relationships between excitatory versus inhibitory learning and the type of control exerted by the experimental context in which these conditioning experiences are embedded. Elimination of the contextual supports for the inhibitory association may neutralize the source of suppression or interference and therefore lead to the renewed expression of the excitatory association. Rescorla's claim that conditioned inhibitors do not produce specific behaviors of their own seems unwarranted, although his argument that the expression of conditioned inhibition requires some kind of excitatory background received general support from the work summarized in it.
