Quick Write What is anxiety? Can you describe what anxiety “looks like” from the biological perspective?
Psychology 12 (2.10) Anxiety Disorders (PTSD)
Anxiety disorders Anxiety is a natural reaction to some situations. In fact, it serves an adaptive purpose. What? Anxiety has both a mental and physiological (CNS) component.
Generalized Anxiety Disorder The anxiety of some people is excessive. People who suffer from generalized anxiety disorder generally experience anxiety in most circumstances. They worry about practically anything. This behavior is sometimes called free-floating anxiety. While most of us associate anxiety with specific situations, these individuals suffer from anxiety at large.
Post-Traumatic Stress Disorder We are going to focus on one specific type of anxiety disorder: Post-Traumatic Stress Disorder. Has anyone heard of this before? According to the DSM, PTSD is characterized as an episode that “lasts for more than 30 days and develops in response to a specific stressor; it is characterized by intrusive memories of a traumatic event, emotional withdrawal, and heightened autonomic arousal. This may result in insomnia, hypervigilance, or loss of control over anger and aggressive behavior.” What types of stressors do you think this refers to?
Prevalence Rate In the US, there is a prevalence rate of about 1-3 %. Similar to depression, women are roughly twice as likely to suffer from PTSD. Also similar to depression, there is an obvious connection to stress. However, all of those exposed to these stressors don’t necessarily develop PTSD. Additionally, the type of trauma is a key factor: roughly 3% of those personally attacked, 20% of wounded veterans, and 50% of rape victims develop PTSD.
Prevalence in veterans A recognition and emphasis has been specifically placed on veterans in the US since the Vietnam War. In that particular conflict, data seems to show that about 30% of veterans of Vietnam have experienced PTSD at some point. Since this time, PTSD has literally been observed in all veteran populations. The findings of the US seem to be supported on a global scale.
Symptoms of PTSD Affective: anhedonia (loss of emotional capacity) Behavioral: hypervigilance, passivity, nightmares, flashbacks, exaggerated startle response. Cognitive: intrusive memories, inability to concentrate, hyperarousal. Somatic: lower back pain, headaches, digestion problems, insomnia, emotional regression, and loss of previously acquired skills.
Etiology of PTSD (Biological) Twin research seems to support genetic predisposition for PTSD. There seems to be a strong connection with noradrenaline (neurotransmitter involved in arousal). Research supports that those experiencing PTSD have higher levels of noradrenaline than average and increased sensitivity of noradrenaline receptors and the adrenal system at large. Is this a logical connection to make?
A group of 74 United States veterans were involved in the study, which for the first time objectively diagnoses PTSD using magnetoencephalography (MEG), a non-invasive measurement of magnetic fields in the brain. It's something conventional brain scans such as an X-ray, CT, or MRI have failed to do . . . With more than 90 percent accuracy, researchers were able to differentiate PTSD patients from healthy control subjects (250 people with clean mental health) using the MEG. All behavior and cognition in the brain involves networks of nerves continuously interacting – these interactions occur on a millisecond by millisecond basis. The MEG has 248 sensors that record the interactions in the brain on a millisecond by millisecond basis, much faster than current methods of evaluation such as the functional magnetic resonance imaging (fMRI), which takes seconds to record. The measurements recorded by the MEG represent the workings of tens of thousands of brain cells. This recording method allowed researchers to locate unique biomarkers in the brains of patients exhibiting PTSD.
Etiology of PTSD (Cognitive) Cognitive focuses on specifically how individuals cognitively process information (appraisal, interpretation). Patients with PTSD tend to express more helplessness. Seemingly unrelated events can “trigger” flashbacks or involuntary memories of trauma. These stimuli can also activate both physiological and emotional aspects of the memory.
Albert Rizzo Virtual IraqEtiology (Cognitive) Similar to treatment of phobias, technology is currently being used to treat those suffering from PTSD: Albert Rizzo has developed a virtual reality program that assists with patients re-experiencing trauma. This treatment is based on the idea of flooding (over-exposure to stress events). The basic idea is that flooding will lead to habituation (stress reactions will fade; you’ll “get used to it”)
What differentiates those who experience PTSD from those who don’t?Etiology (Cognitive) It seems to be related to cognitive processing: Data produced by the research of Sutker et al. (1995) seems to show that Gulf War veterans who a had a sense of “purpose and commitment to the military had less chance of suffering from PTSD than other veterans.” Similarly, victims of abuse appear less likely to suffer from PTSD if they are able to abdicate responsibility for their traumatic event.
Suefeld (2003) Holocaust Survivors and Attribution Style A sample of Holocaust survivors
Etiology (Sociocultural) The majority of research on PTSD focuses on this perspective: Research seems to suggest that exposure to discrimination can be a predisposing factor in PTSD. Examples: Roysircar (2000) Meta-analysis of literature on Vietnam War veterans. 20.6% of African-American and 27.6% of Hispanic veterans met criteria for PTSD as opposed to 13% of white veterans. In areas of conflict (Bosnia and Rwanda) girls tend to be almost twice as likely to suffer from PTSD.
Etiology (Learning) What about the learning perspective? Can we put it in these terms?
Cultural differences in PTSD According to Western diagnosis (DSM), severe somatic symptoms seem to be atypical. Non-western culbody memory symptomstures seem to exhibit more somatic symptoms ()
Gender considerations in PTSD The prevalence of PTSD seems to vary greatly by gender. Likewise, symptoms seem to differ as well. Men are more likely to “suffer from irritability and impulsiveness whereas women are more likely to suffer from numbing and avoidance”. Differences could reflect types of trauma and/or socialization
Breslau et al. (1991) Longitudinal study of 1007 adults who had been exposed to community violence. DSM criteria were used to evaluate and diagnose as suffering from PTSD or not. Found a prevalence rate of 11.3% in women and 6% in men. Some researchers estimate the rate to be even greater.