Imagine you are eating at a fast food restaurant when suddenly a loud crashing sound reverberates through the space. Glass windows shatter, and shards fly through the air as an out-of-control car careens into the store.
In that moment, your heart races, your breath quickens, and your body tenses as it prepares to respond to the unexpected threat. This automatic reaction is an immediate stress response, a complex set of defense mechanisms that have evolved to protect us from danger.
From our ancestors’ encounters with predators to modern-day challenges, trauma responses help us navigate a world full of potential threats.
All animals possess similar defense mechanisms against threats. However, unlike animals, which typically return to normal functioning once the danger has passed, humans may struggle.
They can become trapped in a recurring pattern of responses associated with the original danger or trauma, even after the traumatic event has concluded.
As a result, humans experience not only immediate responses to trauma but also longer-term trauma reactions.
5 Immediate trauma responses
Humans have developed five innate defense states to protect themselves from harm. These common trauma responses are:
- Freeze-fright (tonic immobility)
- Collapse (collapsed immobility)
These five types of trauma responses are activated automatically when we sense danger and are listed in order of increasing threat imminence.1
The freeze-alert state is the first response when we detect a potential threat.
This response involves a sudden stillness. Ongoing activities are temporarily halted, which allows us to assess the situation and determine the level of danger. At the same time, our heart rate increases, preparing us for possible action.
The freeze-alert response provides an opportunity to assess potential threats while minimizing the risk of detection. It gives us time to evaluate our options and decide whether to engage in active or immobility defenses.
By remaining still, we can determine the best course of action without attracting unwanted attention.
The flight response kicks in when we perceive that the threat is imminent and the best course of action is to escape.
During this state, our sympathetic nervous system takes control, increasing heart rate, respiration, and blood flow to the muscles to prepare for an escape.
The primary goal is to distance ourselves from the threat as much as possible.
The fight response occurs when we believe that our best survival chance is to directly confront the threat.
Like the flight response, our sympathetic nervous system is activated, preparing our body for confrontation.
The difference between the two active responses lies in the distribution of blood flow – toward the legs in flight or to the arms and jaw for a fight. Directing more blood flow to the arms and jaw allows us to engage in aggressive behavior.
Freeze-fright / tonic immobility
Freeze-fright is a state of tonic immobility characterized by extreme fear and physical immobility.2
This response occurs when the threat is imminent, and we perceive that active defenses such as flight or fight are not viable options. There is often a perceived inescapable threat (e.g., entrapment or life threat.)
During freeze-fright, our heart rate is reduced, and the body remains tense and prepared for action while inhibiting movement, giving us the appearance of paralyzing fear or being “scared stiff.”
By inhibiting movement, we may avoid provoking further aggression from the attacker, allowing time for the situation to change or for help to arrive.
Collapse / collapsed immobility
The collapse response is our last line of defense when all other options have been exhausted or deemed futile.
Our body transitions to a hypometabolic state, characterized by flaccid immobility and a significantly decreased heart rate.
This “playing dead” response can deter predators or attackers from continuing their assault, as they may believe their prey is already dead or incapacitated, giving us a chance to recover or escape when the attacker loses interest.
These trauma responses keep us safe in the face of danger. They are instinctual and involuntary, designed to maximize our chances of survival.
Under normal circumstances, when adaptive responses successfully handle a threat, the body processes and metabolizes the neurochemicals associated with arousal. This allows us to gradually return to our optimal state once the threatening stimulus has subsided or vanished.
However, this return to baseline may not always occur after a traumatic experience.
In situations involving toxic stress or prolonged trauma, or when there is a lack of adequate soothing and relational support afterward, one may struggle to re-calibrate their autonomic arousal.
When individuals become trapped in a recurring pattern of responses connected to the original danger or trauma, they may experience ongoing distress, anxiety, and various trauma-related symptoms. The once healthy fight response, for example, becomes an unhealthy fight response.
These symptoms can disrupt daily activities and negatively impact the individual’s overall quality of life.
When these symptoms become severe, they can manifest as post-traumatic stress disorder (PTSD).3
10 Post-trauma reactions
Individuals may react differently in the aftermath depending on the types of events they have experienced. There are, however, some common responses to extreme stress.
Common reactions to trauma include:
Experiencing difficult emotions
The most common responses and emotions following a traumatic event are:4
Some individuals might suppress their emotions due to the fear of losing control over their emotional reactions.
If the trauma is left unresolved, this emotional distress can result in mental health disorders such as depression and anxiety disorder.
Trauma can lead to temporary emotional dysregulation; however, for children exposed to abuse or neglect for an extended period of time, this dysregulation may persist because they cannot develop proper emotion regulation skills.5
Children who have experienced attachment trauma often struggle to regulate the strong emotions evoked by the traumatic event, and this emotion dysregulation can persist into adulthood.
Fear and anxiety in trauma survivors can manifest as hyperarousal and hypervigilance.6
Hyperarousal refers to a state of heightened alertness, sensitivity, and physiological activation. Heightened arousal can lead to sleep disorder, irritability, and restlessness.
Hypervigilance is an intense and persistent state of watchfulness for potential threats or danger, which can make the individual easily startled or constantly on edge.
These heightened states of fear and anxiety can significantly impact a person’s daily functioning and overall quality of life, as they may struggle to regain a sense of safety.
When these emotions become too overwhelming, survivors may resort to maladaptive coping mechanisms resulting in substance use disorder, alcoholism, self-harming behavior, or eating disorder.7
Some people may also show compulsive behavior and self-destructive behavioral patterns.
Some individuals may find that certain social situations trigger trauma memories or emotions. They may develop a tendency to avoid these situations to minimize distress.8
This social avoidance can manifest in various ways, such as declining invitations to gatherings, distancing themselves from friends or family members, or even changing their routines to prevent encountering situations that could remind them of the trauma.
Over time, this avoidance behavior can lead to increased isolation and a diminished support network, further exacerbating their emotional struggles and hindering the recovery process.
Intrusive memories are among the most common symptoms in some trauma survivors. There may be flashbacks where the trauma is relived vividly, as if they are happening now.
Other reactions to trauma can include nightmares about the distressing event.9
Reexperience can also occur through reenactments, whereby trauma survivors repetitively relive and recreate the past trauma in their current lives.12
For instance, individuals who have experienced childhood trauma are more likely to find themselves in abusive relationships during adulthood.
This cycle of recreating traumatic situations can stem from the survivor’s unconscious attempt to make sense of the past or gain a sense of control over the unresolved trauma.
Trauma can lead to dissociation in some people. During dissociation, a person’s thoughts, memories, feelings, and actions are mentally separated.
This mechanism is meant to separate one from distress to survive. However, in severe cases, it may develop into a dissociative disorder.10
Aggressive and violent behavior is common among those who have experienced severe trauma.
For instance, combat-exposed military personnel is associated with physical aggression and violence post-deployment.11
Lack of concentration and memory loss
A traumatized person may face challenges with concentration and memory. The lingering effects of trauma can make it difficult for them to maintain focus on tasks, leading to distractibility and a reduced ability to process information efficiently.
Additionally, memory loss or gaps may occur. This can manifest as difficulty recalling specific details of the stressful event or even broader aspects of their lives during the time surrounding the trauma.13
This memory loss can sometimes be a protective mechanism, as the brain attempts to shield the individual from painful memories.
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