Reconsolidation in a human fear conditioning study: a test of extinction as updating mechanism.

Disrupting reconsolidation seems to be a promising approach to dampen the expression of fear memory. Recently, we demonstrated that disrupting reconsolidation by a pharmacological manipulation specifically targeted the emotional expression of memory (i.e., startle response). Here we test in a human differential fear-conditioning paradigm with fear-relevant stimuli whether the spacing of a single unreinforced retrieval trial relative to extinction learning allows for "rewriting" the original fear association, thereby preventing the return of fear. In contrast to previous findings reported by Schiller et al. (2010), who used a single-method for indexing fear (skin conductance response) and fear-irrelevant stimuli, we found that extinction learning within the reconsolidation window did not prevent the recovery of fear on multiple indices of conditioned responding (startle response, skin conductance response and US-expectancy). These conflicting results ask for further critical testing given the potential impact on the field of emotional memory and its application to clinical practice.