Jonathan Gewirtz, Psychology
Matt Kushner, Psychiatry
"Extinction of fear and anxiety: From bench to bedside."

Hide abstract

     Extinction of fear conditioning is one of most thoroughly studied phenomena in Pavlovian conditioning and refers to the reduction in fear to a conditioned stimulus once that stimulus is no longer paired with an aversive consequence. A variety of forms of evidence suggest that extinction involves learning to inhibit fear rather than an erasure of fear itself. Anxiety disorders are characterized by a persistent and chronic activation of fear systems. This may be attributable, at least partially, to an inability to suppress fear in unthreatening circumstances, i.e., a failure of extinction. Support for this view comes from the fact that exposure therapy – an effective treatment for anxiety – is essentially an extinction procedure. Thus, it may be predicted that a treatment that facilitated extinction in animals would facilitate treatment of anxiety in patients.
      Recent evidence suggests the NMDA partial agonist d-cycloserine does both: it accelerates the rate of extinction learning in rats and it improves the outcome of exposure therapy. In this seminar, Jonathan Gewirtz will review the animal literature on fear, extinction, and d-cycloserine, and Matt Kushner will present clinical data supporting the efficacy of the drug as an adjunct to exposure therapy for obsessive-compulsive disorder.

Suggested reading:

• Kushner, M.G, et al. (2007). D-cycloserine augmented exposure therapy for obsessive-compulsive disorder. Biological Psychiatry, 62, 835-838.
  online viewing
  download 266kb pdf