Novelty-facilitated extinction and the reinstatement of conditional human fear

Although contemporary treatments for anxiety disorders are very efficient in reducing anxiety, return of fear after successful treatment is common which signifies a need for interventions that have a more enduring outcome. A recent laboratory study suggested that novelty-facilitated extinction, a simple modification of standard extinction which involves presenting a novel non-aversive stimulus during extinction, prevents spontaneous recovery, one laboratory analogue of return of fear. The current study assessed whether novelty-facilitated extinction can also prevent reinstatement, a second laboratory analogue of return of fear. Following differential fear conditioning, one group of participants underwent standard extinction training whereas the second was presented with a novel tone after the conditional stimulus that previously predicted the aversive unconditional stimulus (US). Three presentations of the USs alone reinstated differential electrodermal fear responses after standard extinction, but not after novelty-facilitated extinction. Moreover, replicating previous findings, the extent of return of fear was correlated with self-reported intolerance of uncertainty after standard extinction, but not after novelty-facilitated extinction. These results support the proposal that novelty-facilitated extinction training can reduce the extent of return of fear.