Testing a novelty-based extinction procedure for the reduction of conditioned avoidance

Background and objectives Excessive avoidance towards non-dangerous cues is a key diagnostic criterion across anxiety-related disorders. Despite current therapies being successful in reducing such avoidance, relapse rates remain high. Based on recent findings, according to which learned fear responses were reduced after the presentation of the fear stimulus with a novel-neutral event (novel-based extinction), we tested whether novel-based extinction could diminish conditioned avoidance. Methods Forty-six participants completed a Pavlovian acquisition procedure during which two pictures of a spider were presented, one of which (CS+) was always followed by a shock (US), while the other (CS−) was never followed by a US. Next, participants learned that they could avoid the shock by pressing a computer button. An extinction and response procedure followed. During this phase, the control group was presented with both CSs that were not followed by the US. The experimental group encountered both CSs, but the CS+ was followed by a neutral event (i.e., presentation of a tone). Return of avoidance (i.e., button presses) and fear (i.e., US-expectancies and fear-ratings) towards both CSs was tested after three unexpected presentations of the US. Results Similar levels of return of avoidance and explicit fear were found for both groups. Limitations We collected no physiological measures of fear and we assessed only the short-term effects of our manipulation. Conclusions Our results do not support the hypothesis that novelty-based extinction reduces avoidance responses. This study can serve as a first exploration of novelty-based extinction for reducing avoidance and explicit measures of fear