I did my internship at a Veterans Administration hospital at a time when Vietnam veterans were coming into a system many had little trust in. They were suffering from effects that seemed related to their service during the war but it wasn’t always clear what help was really available. By the 1970s it was recognized by the medical and mental health services in the VA that veterans were suffering the psychological as well as the physical aftereffects of combat in a long and difficult war. Indeed, many of the veterans that I worked with were still feeling the psychological effects of their experiences in World War II and Korea.
As far back as the late 1600s a constellation of symptoms including low mood, repetitive thoughts, loss of appetite, anxiety, and insomnia were identified by military physicians as being related to participation in combat. Later military physicians noted similar symptoms in veterans of the American Civil War. War became increasingly brutal and industrialized in World War I and these symptoms became common among soldiers in combat. The disorder was known as “shell shock”. The symptoms were initially attributed to the effect of concussions caused by the massive explosions of artillery shells, which were used by the millions. Some physicians, however, doubted this and began to attribute “shell shock” to psychological factors. Early treatments involved support and return to the battle but many victims were considered to be cowards and were treated harshly. In time it was widely recognized that these symptoms were, in fact, caused by psychological stress. By World War II medical and psychiatric professionals attributed the condition of “shell shock” to the psychological stress of the extreme conditions of combat. Terms such as “combat fatigue” were used and early psychological interventions were successful in returning many soldiers to the war but it was unclear what the long-term impact of these experiences would be. After the horrors of the Vietnam War, a clear connection was drawn between psychological stress and the syndrome now called posttraumatic stress disorder (PTSD).
This was the name used by the American Psychiatric Association in its 1980 Diagnostic and Statistical Manual, third edition, to describe symptoms previously known as “shell shock” or “combat fatigue”. It was recognized that civilians who had undergone terrifying and life-threatening events such as assault, rape, or natural disasters like the destruction of a town by a tornado, could also experience these traumatic effects. Both military personnel and civilians were potential sufferers of PTSD. In recent decades there has been increasing recognition of the impact of psychological trauma on the development of psychological and psychiatric disorders.
Psychological trauma has unfortunately been quite common over the course of human history. A partial list of causes would include war, assault, sexual abuse, domestic violence, child abuse, natural disasters, torture, and bullying of both children and adults. Trauma-related disorders can take a number of different forms. The Diagnostic and Statistical Manual of Mental Disorders, fifth edition, lists the following trauma and stressor related disorders: reactive attachment disorder, disinhibited social engagement disorder, posttraumatic stress disorder, acute stress disorder, and adjustment disorders. Sleep disturbances, typically insomnia, are among the diagnostic criteria for both posttraumatic stress disorder and acute stress disorder.
There are many neural and physiological changes that follow exposure to severe stress (Stahl, 2013). For example, neuronal loss and decreased synaptic connections have been noted in depressive and anxiety disorders such as PTSD. The amygdala is an important brain center that is involved in the regulation of fear and the fight or flight response. The motor responses of flight, fight, and freeze are, at least in part, regulated by activation of the amygdala. The fight or flight response leads to increased release of stress hormones including cortisol and adrenaline. In posttraumatic stress disorder these stress hormone levels may be chronically elevated making the individual more susceptible to future episodes of stress. The serotonin system is involved in the regulation of a number of important brain circuits such as the prefrontal cortex, striatum, and thalamus, all of which are involved in the experience of fear and worry. A decreased level of serotonin, resulting from prolonged and/or intense stress, is a factor in the development of posttraumatic stress symptoms. Fear conditioning also plays an important role. For example, after a war-time experience of extreme fear and stress, later exposure to reminders of that stress such as smelling burning rubber, hearing fireworks explode, or seeing pictures of atrocities can trigger intense, anxiety-inducing memories of the initial combat stress.
Epigenetics is an area of study that has to do with changes that occur in organisms due to alterations in gene expression rather than from modifications of the underlying genetics of those organisms. It is a complex and controversial area of research but it appears that the effects of traumatic stress can induce long lasting changes that lead to alterations in stress hormones that may persist for decades, not only in those who actually experienced the extreme stress, but may also affect their children. Examples of this would be heightened stress responses in the children of survivors of events such as the atomic bombing of Hiroshima or the Holocaust. The impact of severe stress may thus extend even beyond the generation directly traumatized.
It is clear that many features of traumatic stress impact on and interfere with sleep. The severe anxiety and stress associated with psychological trauma contribute to over-arousal that persists into the night and causes insomnia. Depression is a common disorder following trauma and results in difficulty falling and staying asleep. Frequent and terrifying nightmares disrupt sleep. Even the fear of having nightmares can make it difficult to fall asleep. Medications used to treat depression and anxiety can, in certain cases, negatively affect sleep. In the next post I'll consider in greater detail the interaction between traumatic stress and sleep disorders.
American Psychiatric Association, (2013). Diagnostic and Statistical Manual of Mental Disorders, 5th Ed. American Psychiatric Publishing: Washington, D.C.
Stahl, S. M., (2013). Stahl’s Essential Psychopharmacology 4th Ed. Cambridge University Press: New York.