Posttraumatic Stress Disorder: The Biological Connection

Posttraumatic Stress Disorder has long been thought of as a mere stress disorder, or as "shell shock" that only veterans of war experienced. However, in reality, Posttraumatic Stress Disorder (PTSD) is more than what either of those classifications suggest. In fact, PTSD is different from other anxiety and stress disorders, and it is experienced by more people than just veterans of the war. Nearly 5.2 million adults, ages 18 to 54, in the United States have posttraumatic stress disorder during any given year as a result of various forms of trauma (American Psychological Association, 2005). Furthermore, the effects of PTSD are deeply rooted in biological processes including hormonal response and neural activity. It isn't just a "thought" disorder. A person with PTSD cannot merely shrug it off and forget it or get over it. The interaction of stress, hormones, and the brain all work to create a very complex disorder that effects both brain and body very intensely.

What is Posttraumatic Stress Disorder?

PTSD and Acute Stress Disorder are often mistaken for each other by the general public due to their similarity in symptoms. However, PTSD is only diagnosed if the patient experiences symptoms for longer than a month. Additionally, in contrast to Acute Stress Disorder, Comer (2005) notes that "The symptoms of Posttraumatic Stress Disorder may begin either shortly after the traumatic event, or months or years afterward. (p. 136). As the term "acute" suggests, an Acute Stress Disorder diagnosis is one which lasts only a short amount of time. For lack of a better comparison, Acute Stress Disorder is like an infection, it occurs and goes away after a short amount of time. Using this same example, PTSD is like a chronic infection, coming on and staying on for a rather long time. This is why Acute Stress Disorder is diagnoses for the first month, if the symptoms last past the first month, the patient is then diagnosed with PTSD. Typically, PTSD symptoms come on within three months of the event, with recovery time between six months and up, often depending on treatment and/or life choices after the event. That being said, Harold Cohen, Ph.D (2006), also notes that "Occasionally, the illness doesn't show up until years after the traumatic event."

The symptoms for PTSD include: re-experiencing the traumatic event, intrusive memories about the traumatic event, avoidance; increased guilt, anxiety, and arousal; and reduce responsiveness. Re-experiencing the traumatic even and experiencing intrusive memories about the event are characterized by nightmares, recurring memories, flashbacks to the event. These memories, nightmares, and flashbacks can be extremely vivid and damaging to the individual, because they may feel that they have experienced the even all over again. One PTSD patient described their experience "I can't get the memories out of my mind! The images come flooding back in vivid detail, triggered by the most inconsequential things, like a door slamming or the smell of stir-fried pork. Last night I went to bed, was having a good sleep for a change. Then in the early morning a storm-front passed through and there was a bold of crackling thunder. I awoke instantly, frozen in fear. I am right back in Vietnam..." (Davis, 1992, as qtd. In Comer, 2005).

Avoidance is when the individual avoids people, places, events, and/or objects that remind them of the trauma they experienced. Even conversations, feelings, and thought that are associated with the event are avoided. This can be exceedingly difficult on the social life of the individual; the Suicide and Mental Health Association International notes that feelings of estrangement or detachment, restricted range of emotions (i.e. unable to feel or express love, etc), and a sense of foreshortened future (unable to see a possibility in a career, in love, marriage, unable to foresee a normal lifespan, etc) are also common in PTSD patients (2006). An article on PTSD by Melinda Smith, M.A, Jaelline Jaffe, Ph.D, and Jeanne Segal, Ph.D (2008) relate the story of a motor vehicle accident victim named Wendy who, after the accident "avoids TV, because she never knows when a terrifying scene might occur. She also avoids driving whenever possible, and refuses to go anywhere near the site of the crash."

Increased anxiety and arousal consist of feelings of hyper-vigilance, sometimes referred to by the general public as paranoia; become easily startled, have trouble getting or staying asleep, and experience trouble concentrating. Feelings of guilt may be associated with survivors guilt or with guilt associated with the violation they experienced. The former, survivors guilt, is when the patient experiences "abnormally high levels of guilt for having survived, especially when others - including family, friends, or fellow passengers - have died (Suicide and Mental Health Association International, 2006). Survivor guilt occurs in individuals that have survived a natural disaster, bullying, violent crimes (such as abuse in the family), wars, etc. Think Hurricane Katrina, or any number of wars. Survivors of POW camps, or of a natural disaster when many have died may feel that they too should have perished, or that the survivor should have been someone else.

Another form of guilt may manifest itself in victims of abuse and rape, in which they turn the blame for the crime to themselves. Excessive guilt for being weak and "allowing the crime to happen," low self-esteem, and a vengeful feeling are commonly associated with victims of the aforementioned crimes. These also impair the social and personal life of patients suffering from PTSD. According to Harold Cohen, Ph.D. (2006), PTSD can be accompanied by "depression, substance abuse, and anxiety," may become "easily irritated or have violent outbursts," and in severe cases may also have "trouble working or socializing." Suicidal thoughts or acts may also manifest as in PTSD patients, as may depression.

In children the complexities of PTSD can be compounded by a different set of symptoms including separation anxiety or fear of being separated from a parent or loved one, relapsing for former developmental stages (losing formerly gained skills); experiencing nightmares, most notably those without recognizable content; serious or melancholy play in which aspects of the trauma are acted out or somehow repeated (this can also be present in drawings and stories), irritable and aggressive behavior, body aches and pains with no apparent cause, the development of phobias and anxieties without a logical connection to the trauma (Smith, Jaffe, and Segal, 2008).

What Causes Posttraumatic Stress Disorder?

As mentioned earlier in the paper, PTSD is triggered by a traumatic experience such as combat, violent crime, abuse, kidnapping, rape, a natural disaster, a car or airline crash, or anything else that makes an individual feel their life is at risk, or that they are powerless against what is happening to them. This aspect is understandable, however, what is not understandable is why only a percentage of the people who experience a traumatic event develop the disorder. If the onset of the disorder was only due to experiencing or witnessing a traumatic event, then the entire every man and women who has experienced a traumatic event would develop the disorder. However, this simply isn't the case. Of the approximately 50% of women and 60% of men who report having experienced a traumatic event, only 10% of women and 5% of men actually report developing PTSD (Psychiatric Times, 2005). Instead, mental and medical health professionals believe that there are a number of other factors that affect whether an individual develops the disorder. Among these factors are: biological and genetic factors, personality, childhood experiences, social support, and severity of the trauma.

The biological factors surrounding PTSD are discussed in greater detail in the following section; however, it is important to note the genetics as a factor in the development of the disorder. A study of 4,000 pairs of twins who had served in the Vietnam war revealed that if one twin developed stress disorder related symptoms, an identical twin was more likely than a fraternal twin to develop symptoms as well (True & Lyons, 1999). Current research into the genetics of PTSD suggest that the disorder is a polygenetic disorder, meaning that no single gene is responsible for it, but rather a number of different genes contribute to the onset of the disorder (Koenen, 2005). Research in this area is currently on-going, but researchers have hope of finding definitive answers in this area due to the aforementioned evidence of a genetic link to the disorder.

Another factor believed to be linked to the development of PTSD is personality. As with genetics this area has notable amount of evidence behind it. The theory is that people with poor stress and anxiety coping styles, and/or high stress personalities or attitudes, are more likely than their counterparts with opposite personality profiles to develop PTSD when exposed to a traumatic event. One study conducted in the area in the aftermath of the 1989 hurricane Hugo found that "children who had been highly anxious before the storm were more likely than other children to develop severe stress reactions (Comer, 2005). Darvres-Bornoz et al (1995) also noted that rape victims who were experiencing psychological problems, or who were experiencing significant stress before the victimization, were more likely to develop a stress disorders after the event. Additionally, negative and fatalistic attitudes also tend to put an individual at higher risk for developing a stress disorder because these attitudes tend to make, or heighten, the feeling that their life and it's events are out of their control. This is especially true for victims of violent crimes such as assault, rape, and close friends and relatives of murder victims.

Just as one's personality plays a role in PTSD, so too does one's experiences during childhood. Many of us can name childhood experiences that somehow shaped us, or at least had a significant impact on us; however, not all of us can name a negative experience that made a significant impact on us. Childhood experiences like being abused, assaulted, experiencing a natural or unnatural disaster, and/or witnessing these types of events can lead to higher risk for developing PTSD upon experiencing trauma. One study conducted by the University of Missouri, St. Louis recorded that "Childhood sexual abuse posed a significantly greater risk for subsequent victimization and psychological problems" (Schulz, 1999). Similar results were yielded in a study on veterans with PTSD and pre-military factors that contributed to their development of the disorder. This particular study found "A positive correlation between physical abuse history and severity of combat-related PTSD" (Zaidi & Foy, 1991). These same trends have also been found in people who grew up in poverty-stricken areas, or those with a family member with a psychological disorder (Comer, 2005).

Another factor, social support also plays an important role in the development of PTSD, and even simply dealing with stress. Having a good social support system is important in normal situations in order to maintain a balance, this same concept holds for those who have experienced a traumatic event. Victims of violent crime, rape, and other traumatic events recover faster and commence with life more easily when they feel they are cared for and loved; and when they are treated well by those around them (including medical personnel, law enforcement personnel, and the like). One serious problem with war today is the lack of proper and caring treatment veterans returning home. It is estimated by the U.S Department of Veterans Affairs that 12 to 20 of every 100 soldiers fighting in Iraq will develop PTSD (2008).

Lastly, and very understandably, the severity of the trauma contributes to whether or not the person will develop PTSD. Generally speaking, a fender-bender isn't going to cause an individual such prolonged stress as to develop PTSD. However, experiencing something like the murder of a family member, a severe and deadly natural disaster, a war, etc, are likely to cause traumatize someone, causing such stress and anxiety so as to give then nightmares, recurring thoughts, avoid the places or television programs that remind them of the event, and so on. After the tragedy of September 11^th 13% of adults who had relatives or friends killed or injured in the attack developed PTSD (Schlenger et al., 2002). The severity of the trauma is so important to PTSD development, that a serious trauma can cause PTSD in even the most adjusted and well nurtured of individuals.

It is important to remember the biological connection to each of these reactions. Since the brain regulates emotions, behaviors, and the like, these symptoms clearly illustrate a PTSD brain interaction, and the interaction of the brain and body, which creates the physical symptoms of the disorder.

A Biological Look at PTSD

While PTSD is a psychological disorder, it manifests itself in many biological ways, which include impacting the body and the brain. PTSD patients experience higher than normal levels of the hormones epinephrine, norepinehrine, and the "stress hormone" cortisol. While these hormones are homeostatic in that they produce the "fight or flight" response; continued or long-term exposure to elevated levels causes negative bodily and mental changes. In the body these include a weakened immune system, ulcers, and hypertension. Furthermore, serotonin, a neural hormone that acts as a chemical messenger and thought to have the ability to alter mood, is believed to play a role in PTSD's effects, and lasting power (PTSD Support Services, 2008). This constant autonomic response (fight or flight) also impairs the ability of the individual to utilize emotions as an adaptive measure. Because emotions are stunted or overly represented, the thought process often associated with response to an emotion is skipped. Henline (N.d) describes this phenomenon, "People who suffer with PTSD display action following the emotional arousal that is often interrupted or disconnected with each other," meaning, they don't react to what the brain has processed, but rather react immediately with survival methods. In essence, they react irrationally.

Another key symptom, and a particularly disruptive one to the recovery process, recurring thoughts and memories of the event which make the patient feel as though they are back in the traumatic event again, is liked to natural opiate levels which are higher than average in those with PTSD (PTSD Support Services, 2008). Because of these hormonal changes, and their adverse effect on the body, treating PTSD is extremely difficult and complex. Not only do mental and medical health professionals have to treat the psychological effects of the trauma, they also must control and alleviate the biological symptoms that play a role in creating the pathology.

It is also important to note the co-morbidity risks that come with PTSD. Serotonin is thought to play a role in depression as well as PTSD, and both seem to co-present. Co-morbidity studies are in progress to investigate this link; however, early studies are an indication that the risk for depression and possible suicide in PTSD patients is very real. Also very real is the risk for common negative behaviors that can present with one or both of these disorders, such as excessive alcohol and/or drug use.

A new, and unexpected, biological link to PTSD patient came to light in early 2008 based on a study published in the Journal of Nervous and Mental Disease, a long-term biological link that puts current and former sufferers at greater risk for chronic diseases at some point in their life. According to John Grohol (2008), PTSD was found to be associated with "chronic disease risk factors such as elevated white blood cell counts, and biological signs and symptoms." Of course, research is still in it's early stages, but these finding warn scientists and medical professionals alike of the serious health risks associated with the disorder. PTSD can no longer be written off as a psychological disease that people need to "just get over."

Posttraumatic Stress Disorder and the Brain

Due to the effects of PTSD memories of trauma are generally inaccurately processed, and many of the thoughts and feelings about the event are misconstrued. For example, feelings of guilt about the incident, hyper-sensitivity, hyper-vigilance, and the like manifest in PTSD sufferers because of the effects of PTSD on the limbic system; a portion of the brain responsible for production and maintenance of emotions and behavior associated with self-preservation and survival (Henline, N.d). For example, the hippocampus is responsible for learning and short-term memory creation; however, in PTSD patients the hippocampus is either accelerated or retarded due to glucocorticoid releases from the adrenal glands (Pinel, 2006). Pinel (2006), also notes a shocking fact about the effect of corticosteroids on the hippocampus stating that "...even a period of stress lasting only a few hours can induce structural changes in the hippocampus that last a month or more" (p. 440). Now, consider that a patient is unable to effectively or consistently create short-term memories, naturally their guard is raised. This is thought to be part of the reason why hyper-vigilance and hyper-sensitivity to stimuli is experienced. The persistent release of hormones is neurotoxic, changing and damaging the structure of vital areas of the brain that would normally assist in recovering from stress, another reason for PTSD's long lasting effect on the sufferer.

Aside from the hippocampus, the amygdala has also been linked to stress and PTSD. Like the hippocampus, the amygdala also plays an important role in the body's physical and mental response to stressful and threatening situations (Lundbeck Institute, 2005). The amygdala can be thought of as a sort of conditioning center for fear. It connections fear-inducing situations from the past, with external stimulus, and due to an overactive amygdala in PTSD sufferers, this causes a fearful reaction to stimulus that may be neutral or even positive. Thus, the sufferer is always on edge, always feeling threatened, always feeling fearful. This sort of inaccurate conditioning creates a situation in which almost nothing seems safe for the PTSD sufferer.

Therapeutic Methods

Prompt and proper treatment is essential when dealing with PTSD. According to data gathered via survey the average length of PTSD symptoms in individuals who received treatment is three years with treatment; however, in those who do not receive any treatment, this time was lengthened by two and a half years (Comer, 2005). While these lengths of time do call attention to the need for newer, and hopefully more effective treatments, they also signal the significance and importance in treatment of the disorder.

Currently, PTSD is treated with psychotherapy, medication, or combination therapy which includes both of the aforementioned. When one hears psychotherapy, they most often associate it with a Freudian model,; however, cognitive behavioral therapy or CBT is currently at the forefront in PTSD treatment. One method of CBT is exposure therapy which calls upon the sufferer to revisit mental images, writing, or the scene of the trauma in order to help them face their fears and control them. Another method is cognitive restructuring, a technique in which PTSD sufferers discuss their thoughts on the incident, question them, and replace them with balanced more rational thoughts in order to change their perception of the event. This helps to place them back in control and empower them. Lastly, stress inoculation training aids in reducing the anxiety and distress PTSD sufferers feel. Additionally, this methods teaches appropriate and effective coping skills so that patients can maintain their composure without using inappropriate methods, and eliminate illogical or incorrect thoughts about the event (National Institute of Mental Health, 2008).

Another promising therapy is eye-movement desensitization and reprocessing, or EMDR, in which a therapist instructs a client to make eye movements or other follow other bodily movements or tactile stimulus while recalling the events of the trauma. Eventually the negative thoughts disappear, and the patient then focuses on a positive memory. This is repeated as necessary under the therapist's guidance. The idea behind this rather odd sounding therapy is to eliminate the negative thoughts, thus eliminating the stress, anxiety, and other symptoms, while maintaining a mental balance. The EMDR Institute (2004) reports that, "After EMDR processing, clients generally report that the emotional distress related to the memory has been eliminated, or greatly decreased, and that they gain important cognitive insights." They also go on to note the behavioral and personal changes that also enhance the quality of life of the patient. While this methods sounds like a "quick fix," it is important to remember that like other treatments EMDR is a process, and each negative thought and/or image must be addressed separately, as guided by a therapist. The good news for the aforementioned treatment methods is that they have been rated by Tori DeAngelis of Monitor on Psychology as "Treatments that make a difference" (2008).

The second option for PTSD treatment is medication. Because of the biological impact that PTSD has on the suffer, medication is crucial in treatment of the disorder. While medication cannot cure PTSD, it provides relief from very disruptive symptoms, and can often allow the individual some time to rest. The first of the medications used in PTSD treatment are serotonergic agents are used to counter hyper-vigilance, obsessive thoughts, and insomnia. Such drugs selectively inhibit the reuptake of serotonin which has been shown to relieve or eliminate the aforementioned symptoms.

The use of anti-depressants seems controversial. Some sources cite their use as risky, lacking definitive proof of effectiveness, and/or lacking significant enough improvement to warrant use, as was published in American Family Physician, 2000, written by Lange et al. However, the APA notes that "We know that these drugs (anti-depressants) are effective, but we don't fully understand what they do to the brain over the long term" (U.S Department of Veterans Affairs, 2007). Some very important research is currently underway concerning the use of anti-depressants for PTSD because of the prevalence of the comorbidity between PTSD and depression. While these drugs are currently controversial, the results of current research projects may find them more or less useful than was formerly believed. However, Antiadrenergic agents and benzodiazepines, two types of drugs also commonly prescribed for stress and anxiety disorders have been shown effective treatment for nightmares, hyper-vigilance, rage, irritability, insomnia, and anxiety (Lange et al, 2000).

As mentioned earlier, prompt treatment is key, and as such critical incident stress debriefing is becoming more and more common in the prevention and/or treatment of after-trauma stress. This form preventative treatment involves counseling to normalize reactions to traumatic events, encouraging the expression of one's emotions; and teaching skills for coping with stress, anger, anxiety, grief, and the like. This form of treatment also encourages on-going counseling for severe cases, and others that feel the need to further discuss and express feelings and thoughts surrounding the event. Although this form first on the scene treatment does have the downside of relief workers feeling overwhelmed, "most professionals believe that intervention at the community level is highly useful after a disaster (Comer, 2005).

Current Research

There are a number of different areas of research currently being conducted concerning PTSD. One of these is a 2007 study on mice conducted by Li-Huei Tsai of MIT's Neuroscience department. According to the study, a molecule was found in the brain of mice that "appears to make them forget the fear associated with a traumatic shock" (MediLexicon International Ltd, 2007). Since current therapy for PTSD relies on ridding oneself of the memories of the traumatic event, this new research is thought to be a promising in effectively "curing" PTSD, quite possibly without the months and years of therapy and painful recurring memories.

The National Institute of Mental Health is also funding research aimed at developing medications that target the underlying causes of PTSD in order to prevent the disorder from occurring. In addition to the abovementioned, the NIMH is also researching personality or other factors that make therapeutic methods more personal, and thus more effective for each individual case.

While the research here, and the research mentioned throughout the paper is not by any means exhaustive, they are some of the most notable studies being conducted. Each of these work to better understand PTSD: its causes, symptoms, treatment, and prevention. It is only through research, and education, that PTSD sufferers will finally receive the type of treatment needed to return to normalcy.

PTSD is a significant problem, one of psychology's most confounding and devastating illnesses. The role of the brain in the disorder further complicates it, and the symptoms experienced by the sufferer. Hormones must be regulated and returned to normal, changes reversed, damage repaired if possible. While medication and psychotherapy are implemented as effectively as we currently know how, PTSD is still a devastating disorder, with a long-recovery time. It is the goal of medical and mental health researchers and practitioners to find a "cure." A medication that can restore the brain and body to normal through the regulation of hormones and the restoration of effective and average brain functioning. This is still a long way off, but the current level of attention being paid to biological factors, and the current understanding of the important PTSD-biologic-psychological connection is rapidly increasing the effectiveness of research, diagnosis, and treatment.

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