Unconditional stimulus deflation is stimulus specific

Previous work has demonstrated that repeated presentations of a conditional stimulus (CS) with a weak shock following training with a strong shock can reduce later conditional responding to that CS. While this procedure shares characteristics with extinction, several converging lines of evidence suggest that weak shock exposure, with steps to minimize prediction error between acquisition and the weak shock phase, will have an advantage over extinction to persistently reduce fear behaviors. A similar experiment by Rescorla demonstrated that unconditional stimulus (US) habituation (repeated exposure to the US alone) reduced responding to a CS that previously predicted that US. Here, we apply this same logic to our weak shock procedure to determine if weak shock presentations in the absence of the CS could reduce responding to subsequent presentations of the same CS. In Experiment 1, using a within-subject procedure, we found that the weak shock-driven reductions in CS-elicited behavior did not transfer to a different CS that was not paired with a weak shock. In Experiments 2 and 3, we demonstrated that weak shock presentations in the absence of a CS (in either a novel context or the acquisition context, respectively) did not attenuate later CS-elicited freezing. Together, these results suggest that, like extinction, weak shock presentations reduce fear behavior in a stimulus-specific manner.