Examining a role for unconditional stimulus deflation in delay fear conditioning

Our lab, and others, have recently demonstrated that fear behavior can be weakened following training with a footshock by presenting a weaker version of that footshock (a phenomenon termed ‘unconditional stimulus deflation’ or US deflation). Unlike extinction, US deflation likely functions by modifying the original fear memory potentially making it a more effective candidate for reducing fear and preventing relapse effects often observed following extinction. Here, we adapted our US deflation procedure to a delay conditioning paradigm in order to examine renewal, spontaneous recovery, and reinstatement. We found that while ABA renewal and reinstatement were unaffected by US deflation, spontaneous recovery and AAB renewal were reduced by US deflation. Deflation in the absence of a CS was ineffective at reducing behavior. Our results suggest that prevention of relapse is at least partially dependent on deflation occurring in the either the same context as training or testing when using a delay fear conditioning procedure.