Efficacy of Targeted Memory Reactivation for Enhancing Exposure Therapy

Placebo-Controlled, Randomized, Double-Blind Study of the Efficacy of Targeted Memory Reactivation for Enhancing Exposure Therapy

This study evaluates whether a scent applied during exposure therapy and during subsequent sleep will increase the durability of treatment effects for individuals with fear of spiders, contamination, and enclosed spaces.

Newly acquired memories encoded during wakefulness are spontaneously re-activated during sleep, resulting in synaptic potentiation and strengthening of the re-activated traces. Targeted memory reactivation (TMR) typically involves a period of initial learning in the presence of an olfactory or auditory contextual cue, coupled with later presentation of the cue during sleep to ostensibly facilitate memory reactivation and consolidation. Numerous studies have found evidence of improved task performance subsequent to cue-induced neuronal replay, however application of TMR to treatment of naturally acquired, clinically significant fear has been limited.

The present study will will provide a rigorous test of TMR's efficacy as an augmentative strategy for exposure therapy. It is hypothesized that participants who sleep in the presence of the same odor that they are exposed to during exposure therapy will exhibit reduced fear at follow up, relative to participants who sleep in the presence of a different odor, or a non-odorous control.

Inclusion Criteria:

• Marked anxiety in at least one fear domain (spiders, contamination, or enclosed spaces), as determined by the presence of both:

  1. self-reported peak anxiety of at least 50 on a 100 point scale in response to two behavioral approach tasks
  2. self-report measures meeting the following cutoffs for the target fear:

• Fear of Spiders Questionnaire ≥ 50

• Obsessive-Compulsive Inventory-Revised (Washing Subscale) ≥ 4

• Claustrophobia Screener ≥ 2

Exclusion Criteria:

• Diagnosed sleep disorder
• Current sleep medication usage
• Inability to differentiate two different odors from an indoor scent diffuser
• Current psychotherapy for fear of spiders, snakes, enclosed spaces, or contamination
• Current use of air fresheners, scented candles, or other items with odors related to those used in the study