Phobias and Stress

Published

A phobia is an anxiety disorder characterized by a recurring, excessive fear of a thing or circumstance. Typically, phobias cause a sudden onset of fear and last for longer than six months.

Phobias often start in childhood. A phobia could be anything you were frightened of when you were little, whether it was a real event or an imagined one.

Were you afraid of the dark? Maybe you were afraid of spiders or insects. Did the stories you read before you went to sleep cause you to imagine bears in the closets or tigers under the bed?

In a given year, specific phobias affect approximately 6-8% of people in the Western world and 2-4% of people in Asia, Africa, and Latin America. Social phobia affects approximately 7% of people in the United States and 0.5-2.5% of people worldwide. Agoraphobia affects approximately 1.7% of the population.

Phobia Severity and Stress

Although the exact nature of the relationship is unknown, research suggests that stress can affect the severity of phobias.

In a 2002 study, Kenneth S. Kendler and colleagues discovered that the stress-diathesis model is inappropriate for phobic disorders, implying that stress does not directly cause phobias.

The stress-diathesis model, also known as the vulnerability-stress model, is a psychological theory that attempts to explain a disorder or its trajectory as the result of an interaction between a predisposition for vulnerability, the diathesis, and life-experience stress. A diathesis can be caused by genetic, psychological, biological, or environmental factors.

The effects of 12 negative life events and ten chronic childhood adversities on the onset of agoraphobia, specific phobia, and social phobia were studied by sociologist W. J. Magee.

He discovered that three distinct events – life-threatening accidents, combat in war (for men), and a fire/flood or other natural disaster – have varying effects on the onset of agoraphobia. Furthermore, two chronic childhood experiences have distinct effects on the onset of specific phobias: violence at the hands of one or more adults and verbal aggression between parents. These findings imply that stressful events can precipitate agoraphobia.

In a 1995 paper, Graham Davey, Ian Burgess, and Rachel Rashes found that individuals with simple phobias and panic disorder use more avoidance coping strategies and less cognitive threat devaluation than normal control subjects, implying that people with phobias are more likely to use avoidance strategies when coping with stress.

W. J. Jacobs and Lynn Nadel found in 1985 that certain psychological states make people vulnerable to acquiring fears, suggesting that people may be more likely to acquire phobias during certain psychological states. They examined accounts of human fears and phobias based on current conditioning models using data from adults and found them inadequate. Instead, the characteristics of human phobias resemble the type of learning found during the amnesic period of infancy.

More research is required to fully understand the relationship between stress and phobias.

Fear Overgeneralization

Recognizing threats is an essential function of the human mind – think ‘fight or flight’ – and aided by negative past experiences. However, when older memories are combined with stress, people are more likely to perceive danger in seemingly innocuous situations, according to a 2017 study.

The findings, by researchers from The University of Texas at Austin’s Dell Medical School, New York University, and McGill University, shed light on fear generalization, a key component of anxiety and stress-related disorders.

For self-defence, the human mind employs cues to danger learned over time, but certain circumstances can cause people to misidentify those cues.

“Our research reveals that stress levels and the amount of time since an adverse event promote this type of overgeneralization,”

said Joseph Dunsmoor, lead study author and assistant professor of psychiatry at Dell Medical School at The University of Texas at Austin.

The researchers examined the effects of stress and time on a person’s ability to correctly identify a cue associated with a negative outcome in the study. Participants in the study heard two tones, one followed by a shock that was set by the participant to be “highly annoying but not painful.”

The researchers then played tones in the frequency range of the two frequencies and assessed participants’ shock expectations using self-report and data on skin responses that indicate emotional arousal. When testing the range of tones, half of the participants were methodically primed to have higher cortisol levels via an arm ice bath, while the other half received a control arm bath with room temperature water.

Heightened Fear Responses

The experiment was carried out on two groups of people. The shock expectancy test was administered to one group immediately following the initial shock. The test was given to the second group 24 hours after the initial shock. The stress/control priming activity was performed on both groups immediately before the shock expectancy test.

Stress level had no effect on participants’ fear of shock or accuracy in identifying the associated tone when tested immediately after the initial shock. However, when participants were tested 24 hours later, the stress level increased their fear response and negatively impacted their ability to identify the tone associated with shock.

The group that was tested 24 hours later and did not have elevated cortisol levels only had slightly heightened fear responses and retained the ability to identify the associated tone.

References:
  1. American Psychiatric Association (2013), Diagnostic and Statistical Manual of Mental Disorders (5th ed.), Arlington: American Psychiatric Publishing, ISBN 978-0890425558
  2. Davey, G.C.L., Burgess, I. and Rashes, R. (1995), Coping strategies and phobias: The relationship between fears, phobias and methods of coping with stressors. British Journal of Clinical Psychology, 34: 423-434.
  3. Dunsmoor JE, Otto AR, Phelps EA. Stress promotes generalization of older but not recent threat memories. Proc Natl Acad Sci U S A. 2017 Aug 22;114(34):9218-9223. doi: 10.1073/pnas.1704428114
  4. Jacobs, W. J., & Nadel, L. (1985). Stress-induced recovery of fears and phobias. Psychological Review, 92(4), 512–531.
  5. Kendler KS, Myers J, Prescott CA. The Etiology of Phobias: An Evaluation of the Stress-Diathesis Model. Arch Gen Psychiatry. 2002;59(3):242–248. doi:10.1001/archpsyc.59.3.242
  6. Magee, W. Effects of negative life experiences on phobia onset. Soc Psychiatry Psychiatr Epidemiol 34, 343–351 (1999).

 

Last Updated on February 25, 2023