Do safety behaviors preserve threat expectancy?

Empirical evidence for the detrimental effect of safety behaviors on fear extinction is inconsistent. This fear conditioning study investigated whether the negative effects of safety behavior on extinction learning depend on whether safety behavior precludes the occurrence of threat. In two experiments, participants first underwent fear acquisition. During a subsequent extinction procedure, participants used safety behavior that precluded the occurrence of threat, safety behavior that reduced threat, or no safety behavior. Safety behavior that precluded the occurrence of threat prevented extinction learning in the first and second experiments. Additionally, in the second experiment, safety behavior that reduced threat severity did not prevent extinction for several participants but did prevent it for others. The findings suggest that safety behavior that prevents the possibility of threat prevents extinction, whereas safety behavior that reduces threat does not prevent extinction consistently.