Effects of Stress on Exposure Therapy

This study investigates whether stress can augment exposure therapy outcome in patients with specific phobia (spider phobia).

Stress has been shown to modulate fear extinction. The present study is aimed at investigating whether stress (administered prior to exposure with the socially evaluated cold pressor test) augments exposure therapy outcome in patients with specific phobia (spider phobia). Furthermore, the effects of stress on the generalization of exposure-induced symptom reduction towards untreated fear stimuli (i.e. cockroaches) will be explored. Participants are randomly assigned to the cold or warm water condition of the socially evaluated cold pressor test (SECPT; Schwabe et al., 2008). Thereafter, participants of both conditions receive 45 minutes of in-vivo exposure to spiders. The effects of stress on exposure-based anxiety reductions toward spiders (treated fear stimulus) and cockroaches (untreated fear stimulus to assess generalization of treatment outcome) are assessed on the behavioral, subjective and physiological level at pretreatment, posttreatment (24 hours after exposure) and follow-up (4 weeks after exposure).

Stress Condition: Cold water condition of the socially evaluated cold pressor test (SECPT; Schwabe et al, 2008).

Cold water condition of the SECPT. Participants immerse their hand into ice-cold water (0-3°C). During the SECPT, participants are videotyped and monitored. After the SECPT, participants will receive 45 minutes of in-vivo exposure to spiders

Warm water condition of the SECPT. Participants immerse their hand into warm water (36-37°C). Participants are neither videotyped nor monitored during the whole procedure. After the SECPT, participants will receive 45 minutes of in-vivo exposure to spiders.

During the Behavioral Approach Test (BAT) the closest distance to a spider as well as subjective fear and heart rate is measured.

Pretreatment, Posttreatment, Follow-up (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up)

During the Behavioral Approach Test (BAT) the closest distance to a cockroach as well as subjective fear and heart rate is measured.

Self-report questionnaires assessing fear of spiders will be used. The Fear of Spiders Questionnaire (FSQ) and the Spider Beliefs Questionnaire (SBQ) will be employed. Scores on these scales range from 0 to 108 and 0 to 100, respectively, with higher scores indicating greater fear of spiders.

Pretreatment, Posttreatment, Follow-up (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up)

Self-report questionnaires assessing fear of cockroaches will be used. The Fear of Cockroach Questionnaire and the Cockroach Beliefs Questionnaire will be employed. Scores on these scales range from 0 to 108 and 0 to 100, respectively, with higher scores indicating greater fear of cockroaches.

Pretreatment, Posttreatment, Follow-up (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up)

Manipulation check (SECPT). Saliva will be collected using salivette sampling devices (Sarstedt, Nümbrecht) at different time points to assess free cortisol concentrations and activity of the enzyme alpha amylase

5 times at Pretreatment, 2 times at Posttreatment, 2 times at Follow-up. (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up)

Manipulation check (SECPT). Systolic and diastolic blood pressure (mm/Hg) are measured at different time points

5 times at Pretreatment, 2 times at Posttreatment, 2 times at Follow-up ( (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up)

Inclusion Criteria: Women using oral contraceptives (OC) Specific phobia (spider phobia) Exclusion Criteria: Body Mass Index (BMI) < 19 or > 27 Pregnancy Any acute or chronic mental, somatic, endocrine, or metabolic disease Psychological, psychiatric, neurological or pharmacological treatment Shift work Smoking more than 5 cigarettes per month Vaccination in the past 2 month Drug or alcohol abuse

Schwabe L, Haddad L, Schachinger H. HPA axis activation by a socially evaluated cold-pressor test. Psychoneuroendocrinology. 2008 Jul;33(6):890-5. doi: 10.1016/j.psyneuen.2008.03.001. Epub 2008 Apr 9.