Generalized Fear Extinction to Untreated Fear Stimuli in Specific Phobias After Exposure
Condition: Fear of Spiders; Fear of Heights
MeSH terms: Phobic Disorders
Study type: Interventional

Summary: 
      This study investigates whether a one-session exposure treatment for spider-related stimuli
      can lead to a generalization of extinguished fear to height-related stimuli in individuals
      with comorbid fear of spiders and fear of heights.
    

Detailed description: 
      Exposure therapy has been proven to be effective in the treatment of specific phobias and in
      a variety of fear evoking situations and stimuli. However, since there is a high prevalence
      of comorbid fears, therapeutic interventions can get very extensive when each fearful
      situation and / or stimuli needs to be treated separately and over a repeated number of
      times. It has recently been shown, that exposure to one fearful stimuli (i.e., a spider), can
      also lead to a reduction of fear to another, perceptually and conceptually related, but
      untreated fearful stimulus (i.e., a cockroach) (Preusser, Margraf & Zlomuzica, 2017).
      Potentially, this generalization of exposure effects might also be relevant for coexisting
      fears that do not share conceptually related fearful stimuli (e.g., fear of spiders and fear
      of heights). The present study aims to investigate whether successful exposure treatment to
      one fearful stimulus (i.e., a spider) can also lead to a reduction of fear to an untreated
      fear evoking stimulus (i.e., height).

      Participants will be randomly assigned to the treatment or no-treatment condition. The entire
      experimental procedure will take place in three sessions. The first session incorporates
      spider and height fear related questionnaires and two Behavioral Approach Tests (BATs): One
      that involves a spider and one that involves height. These BATs are counterbalanced in each
      group with half of participants receiving the spider BAT first and the height BAT second, and
      vice versa. The second session takes place approximately seven days later. The treatment
      group receives a seven-step in vivo exposure with spiders (duration: 1,5 hours). Twenty-four
      hours later, session 3 takes place and involves the same measures that were applied in
      session 1. The treatment and no-treatment group receive an identical set of measures except
      that the no-treatment group will not be subjected to exposure. The effects of exposure-based
      anxiety reductions toward spiders (treated fear stimulus) and heights (untreated fear
      stimulus to assess generalization of treatment outcome) are assessed on the behavioral and
      subjective level at pretreatment and posttreatment (24 hours after exposure).
    

Intervention name(s): Exposure
Intervention type(s): Behavioral
Intervention description(s): The exposure session comprises a hierarchy of 7 steps, reaching from (1) holding a glass with the spider 30cm in from the body / face, to (7) letting the spider walk on the arm. The exposure session has a duration of 120 minutes. Prior to the exposure, participants receive psychoeducation on anxiety and phobias. A house spider (Tegenaria domestica) is used for the exposure.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: Exposure Therapy; Fear of Spiders; Fear of Heights; Anxiety Disorders; Generalization; Extinction; Specific Phobias