Starting from something: Augmenting exposure therapy and methods of inquiry

摘要

In this issue of the Journal, Telch et al. (1) examine the ability of methylene blue to augment extinction learning in individuals with claustrophobic fear. The authors studied 42 individuals randomly assigned to double-blind administration of 260 mg of methylene blue or placebo following multiple extinction trials in an enclosed chamber over the course of one clinical session. The primary outcome is self-rated peak fear (scale: 0-100 points) upon re-entry into a similar enclosed chamber a month later. The authors correctly hypothesize extinction augmentation only for those who report low end-state fear subsequent to extinction training; the primary interaction and follow-up analysis effects are large and statistically significant. Marginally supportive evidence is also found for a hypothesized deleterious effect of the medication on those with high end-state fear subsequent to extinction training. The authors include a free-recall contextual learning test to examine the impact of medication on learning in general and find positive hypothesized effects. In other words, methylene blue improved recall of nonfear-related stimuli for the entire medication group but only improved outcomes for those with low end-state fear after exposure. The take-home message is that methylene blue is related to enhanced contextual learning in general. Accordingly, learning is enhanced regarding whatever takes place; if exposures are successful, the successful learning is enhanced, if unsuccessful, learning related to the negative experience is enhanced.