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Exploring human freeze responses to a threat stressor
Norman B Schmidt1, J Anthony Richey, Michael J Zvolensky
1Department of Psychology, Florida State University, Tallahassee, FL 32306, USA. schmidt@psy.fsu.edu
Journal of Behavior Therapy and Experimental Psychiatry
|September 21, 2007
Summary
Human freeze responses, a key part of anxiety, were studied using a CO2 challenge. Researchers found that subjective anxiety and panic predicted this immobility response in 13% of participants.
Area of Science:
- Psychology
- Neuroscience
- Human behavior
Background:
- Tonic immobility is a fundamental anxiety response, yet human "freeze" behavior is under-researched.
- Understanding the freeze response is crucial for anxiety and trauma research.
Purpose of the Study:
- To investigate the frequency and predictors of the human freeze response.
- To examine the freeze response during a biological challenge.
Main Methods:
- A nonclinical sample (N=404) was exposed to a 20-second inhalation of 20% CO2.
- Participants reported perceptions of immobility and desire to flee.
- Anxiety and panic levels were assessed during the challenge.
Main Results:
- 13% of participants reported a "freeze" (immobility) response.
- 20% reported a desire to flee.
- Subjective anxiety, panic, and specific anxiety symptom dimensions predicted the freeze response.
Conclusions:
- The human freeze response occurs in a significant minority during acute biological challenges.
- Anxiety and panic are key psychological correlates of the freeze response.
- Further research is needed to fully elucidate the human freeze response in various contexts.
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