"We have learned that trauma is not just an event that took place sometime in the past; it is also the imprint left by that experience on the mind, brain, and body."
- Bessel van der Kolk, "The Body Keeps the Score"
Recognize the symptoms of trauma
Trauma is not just a psychological problem...
As an extreme form of stress, trauma activates of the body's stress response system. As the body adapts to unprocessed trauma over time, chronic activation of the stress response leads to dysregulation across the nervous system and its associated networks, which manifests as common medical symptoms.
Recognizing the symptoms of nervous system dysregulation will allow practitioners to include trauma within their differential diagnosis, and recommend more effective treatments.
Stress Physiology 101
The Stress Response System
The Stress Response System consists of a network of structures throughout the brain and nervous system whose primary function is to prepare the body's response to threat. This network includes the prefrontal cortex (responsible for attention, impulse control and cognitive flexibility), the amygdala (the emotional/fear processing center in the brain) and the autonomic nervous system (controls all the involuntary functions in the body including heart rate, breathing, digestion and repair functions).
Under non-stress conditions, the prefrontal cortex modulates the activity of the amygdala. This provides conscious control over a potential fear response generated by the amygdala, which would otherwise activate the autonomic nervous system to respond to a perceived threat. In this way, the prefrontal cortex is able to control our behavioral (and sometimes our physiological!) responses. This is the rationale behind Cognitive Behavioral Therapy.
Under conditions of stress, however, the prefrontal cortex is inhibited, allowing the amygdala to "hijack" conscious behavioral control and our physiological response. Under perceived threat, the activated amygdala triggers a cascade of neurological and hormonal responses aimed at maximizing energetic efficiency and increasing our chance of survival. These responses include:
- Reduced parasympathetic vagal activity
- Increased sympathetic activity
- Release of cortisol from the adrenal glands
This is an innate response designed to promote survival, and is not under conscious control.
The Sympathetic Nervous System (Flight or Flight response)
When you think the body’s response to threat, most people think about the effects of the sympathetic nervous system, or the “Fight or Flight” response. The sympathetic nervous system creates a state of hyperarousal in the body, which allows it to “mobilize” in response to threat. That is to say, everything that allows the body to fight or run away such as: increased heart rate, increased breathing rate, pupillary dilation, increased availability of glucose, and increased blood flow to muscles.
The Parasympathetic Nervous System (Faint or Freeze response)
In order to conserve energy, and allow the sympathetic nervous system to execute its functions, the parasympathetic nervous system effectively takes a back seat in the face of threat. The vagus nerve reduces its activity which, under conditions or rest or safety, is responsible for keeping the heart rate low and regulating the important functions of digestion, reproduction, immunity and repair. Most practitioners learn very little about the parasympathetic nervous system, other than a simple acronym “Rest, Digest, and Repair”. This acronym only scratches the surface of the critical functions of the vagus nerve, whose sole purpose is to keep the body healthy.
Although vagal nerve activity is reduced in the initial stages of the stress response, when the amygdala registers profound fear, or feelings of helplessness, the vagus nerve can become over-active, creating a generalized state of hypoarousal throughout the body. This is known as “Faint or Freeze” or the collapse response, and is characterized by bradycardia, motor paralysis, physical and emotional numbing, and psychological dissociation. This can be readily observed by lizards, opossums or gazelles who "play dead", but also occurs in humans (consider the response to people who faint at the site of blood). Interestingly, this innate and involuntary response also serves to increase the chance of survival by reducing circulation, which decreases the chance of death by exsanguination, and creating confusion for predators who expect live prey, creating the opportunity for escape.
Wired for threat
To live with trauma or toxic stress is to experience a subjective state of perpetual threat. This is sometimes recognized through the symptoms of Post-Traumatic Stress Disorder (PTSD), such as intrusion, avoidance, negative changes in thought and mood, and changes in arousal or reactivity. However, since PTSD was first defined as a psychiatric condition, the DSM-V diagnostic criteria are limited to behavioral and cognitive characteristics. In fact, many of the associated symptoms of PTSD are also physiological.
These physiological changes reflect dysregulation of the networks across the stress response system, namely the cortical, limbic, and autonomic networks, which have adapted to a perpetual state of threat over time. In response to chronic stress or trauma, the autonomic nervous system may generate a state of persistent hyperarousal (through activation of the sympathetic nervous system), a state or persistent hypoarousal (through activation of the parasympathetic nervous system), or may fluctuate between these two extremes. Prolonged activation of these neural networks results in a new baseline for the nervous system through the process of neuroplasticity.
Some of the physiologically-based symptoms that relate to dysreguation across the stress response system and its end organs include:
Cognitive dysregulation: "brain fog", inattention, poor impulse control, cognitive inflexibility
Limbic dysregulation: anxiety, panic attacks
Respiratory dysregulation: short, shallow breathing pattern, sensation of "air hunger", dyspnea
Cardiovascular dysregulation: heart palpitations, hypertension
Autonomic dysregulation: dizziness, syncope, blurred vision
Somatic dysregulation: Chronic pain, migraine, conversion disorder, functional neurological deficit
Enteric dysreguiation: Gastroesophageal reflux, constipation
Sleep dysregulation: insomnia, frequent night wakings, sleep-disordered breathing
These symptoms often co-exist with Post-Traumatic Stress Disorder, but rather than seeing them as "associated symptoms", these can be understood as symptoms of physiological dysregulation that requires alternative treatment. Such treatments may include techniques that promote regulation, such as breathing, exercise, emotional regulation, or heart rate variability biofeedback .
