By What is the polyvagal theory? How does the polyvagal theory explain our response to a traumatic event? We will tell you in this article!
For Stephen Porges, the polyvagal theory and trauma are inseparable . This theory explains how our body reacts to traumatic events. Thus, it emphasizes that the nervous system has more than one defense strategy against danger. It does not only have the classic fight/flight strategy. Without being aware of it, the brain is constantly evaluating the risk in our environment, minute after minute, day after day.
For some people it is the physical characteristics of what they see, hear or smell that trigger fight/flight behavior, while other people may not respond to the same stimulus in the same way. Thus, the crucial factor is not the traumatic event, but the response to it.
“Trauma is often defined and treated as a general category of stress-related disorders. In doing so, we miss out on much of how our bodies respond to situations that are assessed as potentially life-threatening.”
-Porges-
Trauma from the polyvagal theory
The polyvagal theory attempts to explain how the autonomic nervous system (ANS), the way we regulate and express emotions, and our way of behaving socially are related and influence each other. It identifies three levels or hierarchical systems:
- First level . Contains the biologically oldest defense system : the immobilization response. What part of the brain controls it? The dorsal motor nucleus of the brain stem. This level can be found in animals with a less evolved nervous system, such as reptiles.
- Second level . It contains a somewhat more refined defense system: fight or flight. What part of the brain controls it?: the sympathetic nervous system . This level appears for the first time in mammals.
- Third level . Contains the most sophisticated system: the social response or engagement. It is the system responsible for cooperative interpersonal behavior. What part of the brain controls it? A recent one in evolutionary terms: the ambiguous nucleus of the brain stem. It is a level that is highly developed in higher primates and in humans.
For some individuals, what might be considered a traumatic event is just another occurrence. For others, however, it is a threatening event that directly endangers their lives, triggering coping responses in the body: they react as if they were going to die.
It is currently unknown how our circuits decide which situations are safe or not. In a pedagogical sense, we could say that when faced with threats in our environment, if we are protected with the third level, the newest level, we do well.
“Early experiences probably play an important role in changing the threshold or vulnerability for maladaptive reactions to traumatic events.”
-Porges-
For example, when faced with a sexual abuse experience, the oldest vagal circuit can be activated: immobilization. What happens is that we do not have conscious control of this circuit. As a consequence, we can “disconnect”: we can faint.
In therapy, people who talk about abuse, especially sexual abuse, have the experience of being physically abused or subjected to abuse. The description they typically give is of not really being there: they black out or dissociate .
Neuroception: a key concept of polyvagal theory in relation to trauma
Neuroception is sensing without awareness. Perception requires awareness of what is being perceived, neuroception does not. It is sensing something without being aware of it. It is the level of the brain that monitors, evaluates and detects the degree of threat that each of the elements we perceive may pose to us. Neuroception highlights our third system: the social engagement or cooperation system.
The work of the third system can influence our “more primitive” defenses, but when the risk increases, the first two systems take over. In response to a potential or real danger, the first and second systems trigger a cascade of metabolic, hormonal and neural reactions so that we can fight or flee.
When the social cooperation system is working and down-regulating our defenses, we feel calm.
The same traumatic event can trigger different neuroceptive reactions. We know that traumatic events produce dissociation. To dissociate is to separate. It is to break something. Often, what remains separated is, on the one hand, the story of the traumatic event and, on the other, the sensory characteristics: the acoustic signals, the smells, the colors or the flavors.
Thus, today we know that one of the most powerful triggers of neuroception (unconscious detection) is acoustic characteristics.
The Listen project
The Listen project is an intervention project that is investigating whether training the muscles of the middle ear can help people who have suffered trauma.
The polyvagal theory supports the hypothesis that if we begin to influence our third system, the social cooperation system, and train the muscles of the middle ear – important for the detection of acoustic characteristics – we will be more skilled at distinguishing the human voice from the rest of the stimuli, which will help the person to be more social spontaneously.
The goal is to create auditory hypersensitivity. The idea is that by increasing our sensitivity to human voices, we become more sociable. Our third response system is activated more, making it less likely that we will experience an event as traumatic.
In general, human beings are very adaptable to the circumstances in which we find ourselves. If we come from a family in which our parents are depressed, or chaotic, we will adapt to not get involved; and, therefore, we will be down-regulating or turning off our third system: that of social cooperation.
Furthermore, this theory could shed more light on certain psychiatric illnesses and disorders that are related to failures in the regulation of the three systems, such as trauma, dissociative identity disorder or borderline personality disorder .