In Experiment 1, control of instrumental responding by deprivation-intensity cues was demonstrated. Rats anticipated the occurrence of punishment in the goal box when the occurrence of punishment was predictable on the basis of degree of food deprivation (a food reward was given on all trials). In Experiment 2, control of instrumental responding by deprivation-intensity cues was measured separately from other effects of deprivation, by correlating the occurrence of food reward or nonreward with deprivation intensity. Half of the rats received food reward under high deprivation and nonreward under low deprivation; the other half received the reverse deprivation-goal event correlation. Initially, rats run faster on all trials, the higher the deprivation under which reward was experienced, an effect suggesting that food produces stronger conditioning or is more reinforcing or produces greater incentive, the higher the deprivation under which it is experienced. Later in training, rats ran more rapidly under their rewarded deprivation than under their nonrewarded deprivation whether their rewarded deprivation was high, low, or very low. These results indicate that deprivationstimulus-intensity cues can exert strong control over instrumental responding and that this effect occurs later in training than the effects of deprivation on reinforcement or incentive. The theoretical and practical implications of these findings are discussed.

In three experiments, counterconditioning was found to reduce fear less effectively than extinction. In Experiments 1 and 2, the resistance to extinction of avoidance was greater if food was given during extinction of fear to the CS than if no food was given, even when exposure to the CS and numbers of food and no food confinement trials were equated. It is suggested that these results could be attributed to contextual control of fear extinction by the food cue and/or to frustration produced by removing food for the counterconditioning group. Experiment 3 also found counterconditioning to be less effective than extinction and provided evidence that this difference occurs because of contextual control of fear extinction by the food cue. Measuring conditioned suppression of licking, in a test with no food present, less fear was shown if no food had been present during fear extinction, and greater fear was shown if no food had been present during fear conditioning. These results indicate that food is an important part of the context controlling fear and fear extinction. It is suggested that there may be no unique counterconditioning process. Rather, when counterconditioning procedures are employed, rules governing interference paradigms in general may apply. Thus, in a test for fear following counterconditioning, fear will be shown to the extent the test situation is similar to that in which fear conditioning occurred rather than that in which fear reduction occurred.

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