Learning Objectives
- Describe the biological causes of trauma- and stressor-related disorders.
- Describe the cognitive causes of trauma- and stressor-related disorders.
- Describe the social causes of trauma- and stressor-related disorders.
- Describe the sociocultural causes of trauma- and stressor-related disorders.
Biological
HPA axis. One theory for the development of trauma and stress-related disorders is the over-involvement of the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis is involved in the fear-producing response, and some speculate that dysfunction within this axis is to blame for the development of trauma symptoms. Within the brain, the amygdala serves as the integrative system that inherently elicits the physiological response to a traumatic/stressful environmental situation. The amygdala sends this response to the HPA axis to prepare the body for “fight or flight.” The HPA axis then releases hormones—epinephrine and cortisol—to help the body to prepare to respond to a dangerous situation (Stahl & Wise, 2008). While epinephrine is known to cause physiological symptoms such as increased blood pressure, increased heart rate, increased alertness, and increased muscle tension, to name a few, cortisol is responsible for returning the body to homeostasis once the dangerous situation is resolved.
Researchers have studied the amygdala and HPA axis in individuals with PTSD, and have identified heightened amygdala reactivity in stressful situations, as well as excessive responsiveness to stimuli that is related to one’s specific traumatic event (Sherin & Nemeroff, 2011). Additionally, studies have indicated that individuals with PTSD also show a diminished fear extinction, suggesting an overall higher level of stress during non-stressful times. These findings may explain why individuals with PTSD experience an increased startle response and exaggerated sensitivity to stimuli associated with their trauma (Schmidt, Kaltwasser, & Wotjak, 2013).
Cognitive
Preexisting conditions of depression or anxiety may predispose an individual to develop PTSD or other stress disorders. One theory is that these individuals may ruminate or over-analyze the traumatic event, thus bringing more attention to the traumatic event and leading to the development of stress-related symptoms. Furthermore, negative cognitive styles or maladjusted thoughts about themselves and the environment may also contribute to PTSD symptoms. For example, individuals who identify life events as “out of their control” report more severe stress symptoms than those who feel as though they have some control over their lives (Catanesi et al., 2013).
Social
While this may hold for many psychological disorders, social and family support have been identified as protective factors for individuals prone to develop PTSD. More specifically, rape victims who are loved and cared for by their friends and family members as opposed to being judged for their actions before the rape, report fewer trauma symptoms and faster psychological improvement (Street et al., 2011).
Sociocultural
As was mentioned previously, different ethnicities report different prevalence rates of PTSD. While this may be due to increased exposure to traumatic events, there is some evidence to suggest that cultural groups also interpret traumatic events differently, and therefore, may be more vulnerable to the disorder. Hispanic Americans have routinely been identified as a cultural group that experiences a higher rate of PTSD. Studies ranging from combat-related PTSD to on-duty police officer stress, as well as stress from a natural disaster, all identify Hispanic Americans as the cultural group experiencing the most traumatic symptoms (Kaczkurkin et al., 2016; Perilla et al., 2002; Pole et al., 2001).
Women also report a higher incidence of PTSD symptoms than men. Some possible explanations for this discrepancy are stigmas related to seeking psychological treatment, as well as a greater risk of exposure to traumatic events that are associated with PTSD (Kubiak, 2006). Studies exploring rates of PTSD symptoms for military and police veterans have failed to report a significant gender difference in the diagnosis rate of PTSD suggesting that there is not a difference in the rate of occurrence of PTSD in males and females in these settings (Maguen, Luxton, Skopp, & Madden, 2012).
Key Takeaways
You should have learned the following in this section:
- In terms of causes for trauma- and stressor-related disorders, an over-involvement of the hypothalamic-pituitary-adrenal (HPA) axis has been cited as a biological cause, with rumination and negative coping styles or maladjusted thoughts emerging as cognitive causes.
- Culture may lead to different interpretations of traumatic events thus causing higher rates among Hispanic Americans.
- Social and family support have been found to be protective factors for individuals most likely to develop PTSD.
Review Questions
- Discuss the four etiological models of the trauma- and stressor-related disorders. Which model best explains the maintenance of trauma/stress symptoms? Which identifies protective factors for the individual?
