Secondary extinction reduces reinstatement of threat expectancy and conditioned skin conductance responses in human fear conditioning

• Published in: Journal of behavior therapy and experimental psychiatry 2019-03, Vol.62, p.103-111
• Main Authors: Mertens, Gaëtan, Leer, Arne, van Dis, Eva Anna Maria, Vermeer, Lotte, Steenhuizen, Anne, van der Veen, Lisa, Engelhard, Iris M.
• Format: Article
• Language: English
• Subjects: Adult; Behavior modification; Conditioning; Conditioning, Classical - physiology; Electrical stimulation; Experimental psychology; Exposure therapy; Extinction; Extinction, Psychological - physiology; Fear & phobias; Fear - physiology; Fear conditioning; Feasibility; Female; Galvanic skin response; Galvanic Skin Response - physiology; Humans; Male; Manipulation; Psychological extinction; Rats; Reinstatement; Secondary extinction; Sensitivity; Skin conductance response; Stimulus; Stimulus equivalence; Young Adult
• ISSN: 0005-7916; 1873-7943
• DOI: 10.1016/j.jbtep.2018.09.007

Secondary extinction refers to the phenomenon that extinction of one conditioned stimulus (CS) results in the reduction of conditioned responses for other CSs conditioned with the same unconditioned stimulus (US). Previous research with rats has demonstrated that secondary extinction can interfere with the return of conditioned fear after a reinstatement manipulation. Here we investigated this phenomenon in two pre-registered studies in humans. In both experiments, distinct CSs were paired with an electrical stimulation. Next, conditioned reactions to both CSs were extinguished and thereafter reinstated through the administration of three unsignaled electrical stimulations. Crucially, before participants continued with the reinstatement test, half of the participants received secondary extinction trials whereas the other half did not receive these trials. Our results indicate that secondary extinction reduced reinstatement of threat expectancies and skin conductance responses, but the effect on skin conductance was only found in the second experiment. The studies were conducted in a laboratory setting with healthy students. Additional research will be required to determine the feasibility of applying secondary extinction in a (sub)clinical context. To our knowledge, this is the first demonstration of secondary extinction and its effect on reinstatement of conditioned fear in humans. We relate our findings to the earlier research with rats and discuss their relevance for exposure therapy. •Unreinforced presentation of one CS can reduce the reinstatement of another CS.•This secondary extinction phenomenon was previously demonstrated with rats.•Here we replicate this phenomenon in two preregistered human fear conditioning studies.•Our results indicate several important moderators of this phenomenon.•We discuss the relevance of secondary extinction for exposure therapy.