Biobehavioral Correlates of Acute Phobic Fear

Study Overview
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Brief Summary
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This study seeks to measure the time course of circulating proinflammatory markers (interleukin-1 beta [IL-1β], interleukin-6 [IL-6], tumor necrosis factor alpha [TNF-α], and C-reactive protein [CRP]) and salivary alpha amylase (sAA) following laboratory fear arousal. Further, this study seeks to implement neurocognitive, physiological, and self-report measures to explore the role of threat sensitivity as a predictor of this response. The broad research question seeks to better understand the relationship between neurocognitive fear and subsequent stress responding elicited by both the immune system (i.e., proinflammatory markers) and autonomic nervous system (i.e., sAA). In light of these aims, the primary outcomes of the current study are the proinflammatory markers (IL-1β, IL-6, TNF-α, CRP), while secondary outcomes consist of sAA, neurocognitive measures (i.e., dot-probe task), physiological correlates (i.e., heart rate, galvanic skin response), and self-report measures.

Official Title
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Biobehavioral Correlates of Acute Phobic Fear: Proinflammatory, Autonomic, and Neurocognitive Outcomes

Conditions
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Phobia

Intervention / Treatment
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* Behavioral: Fear tasks


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 - 40 years old Phobic or nonphobic fear of spiders. Willing to proceed through 5-stimulus fear hierarchy or maintain 7 or higher subjective units of distress through fear task (see Procedures section). Exclusion Criteria: Lifetime history of serious mental illness Lifetime history of intellectual or developmental delays Lifetime history of chronic physical or medical illness including blood clotting disorders Lifetime history of allergies to latex Lifetime history of hormonal replacement therapy Lifetime history of blindness Lifetime history of blood/injection phobia or aversion to needles/injection (based on IPS-Anx and MQ) Substance abuse in the past 2 years Cigarette/tobacco use in the past 2 years Major depression within the past 12 months Traumatic stress within the past 12 months Pregnancy within the past 12 months Anesthesia within the past 3 months Night shift work within the past month Use of medication within the past month (except for oral contraception) Acute illness or infection within the past month Average sleep outside of 6 - 10 hours per night within the past month Average intake of 4 or more alcoholic beverages per week Average intake of 6 or more cups caffeine per day Use of marijuana within the week before the laboratory session Use of alcohol within the week before the laboratory session Body mass index outside of 18.5 - 24.9 range

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Phobic<br>Adults aged 18-40 exhibiting high levels of self-reported phobic symptoms to spiders | Behavioral: Fear tasks<br>* All participants will be exposed to 5 fear tasks involving spiders, with increasing fear intensity.<br>|
| Nonphobic<br>Adults aged 18-40 exhibiting low levels of self-reported phobic symptoms to spiders | Behavioral: Fear tasks<br>* All participants will be exposed to 5 fear tasks involving spiders, with increasing fear intensity.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood plasma concentration of IL-1 beta | interleukin-1 beta (pg/mL) via blood draw | 4 hours | 
| Blood plasma concentration of IL-6 | interleukin-6 (pg/mL) via blood draw | 4 hours | 
| Blood plasma concentration of TNF-alpha | Tumor necrosis factor-alpha (pg/mL) via blood draw | 4 hours | 
| Blood plasma concentration of CRP | C-reactive protein (mg/L) via blood draw | 4 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Autonomic marker: alpha amylase | salivary alpha amylase | 50 minutes | 
| Autonomic marker: galvanic skin response | galvanic skin response (GSR) via Empatica E4 wristband | 4 hours | 
| Autonomic marker: heart rate | heart rate variability (HRV) via Empatica E4 wristband | 4 hours | 
| Threat sensitivity: neurocognitive task | exogenous cueing task via PsychoPy | 10 minutes | 
| Threat sensitivity: self-report | Clinician-Administered PTSD Scale for DSM-5 (CAPS-5); 6 items (B4, B5, D4, D5, C1, C2) reworded for spider phobia | 10 minutes |