Understanding The Neurobiology of Trauma

By Emma Heffer, I Have The Right To Intern

Understanding the neurobiology of trauma is crucial for recognizing how traumatic events affect the brain, which helps validate survivors’ experiences and inform effective healing strategies. It explains why trauma survivors may react with involuntary stress responses, such as being hypervigilant or emotionally dysregulated, and helps debunk harmful myths and reduce stigma by reframing these reactions as biological coping mechanisms rather than character flaws. This knowledge is essential for developing targeted therapies that help the brain feel safe again.

The neurobiological effects of a traumatic experience are typically centralized in the prefrontal cortex. The prefrontal cortex is the part of the brain responsible for decision-making and rational thinking. When functioning properly, it helps us to plan effective responses and remember important information. During day-to-day life, the functions of the prefrontal cortex are typically undisturbed and aid us in completing our daily tasks, but when a person is experiencing a traumatic event, their “Fear Circuitry” may take control. “Fear Circuitry” represents the lesser-known third element of the “fight or flight” response: freeze. A commonly known example of this response is the deer in headlights phenomenon, where the deer’s prefrontal cortex is confronted with the fear of being threatened by an oncoming car; their Fear Circuitry takes over, causing them to freeze in the middle of the road. 

Humans have this same fear response, and in reality, freezing is the most common reaction to trauma, rather than fighting back or running away. This subconscious survival instinct reveals the neurobiology behind the range of responses to sexual assault or any form of abuse. It explains why victims often find themselves unable to escape a situation or even attempt to fight back. Often, it is not a matter of choice; instead, your brain slips into survival mode, allowing fear circuitry to override the prefrontal cortex. 

Furthermore, some survivors may experience more extreme survival reflexes, such as tonic immobility or collapsed immobility. These responses are more similar to an animal, such as a possum, going limp when it is scared. The sensation of going limp, feeling “sleepy”, passing out, or being unable to move at all are all survival mechanisms that are hardwired into our brains. These feelings are caused by a drop in blood pressure and heart rate, leading to muscle limpness and a lack of oxygen to the brain.

As an additional protection mechanism, survivors may also experience mental dissociation, which is typically described as going into “auto-pilot” mode. In this mode, individuals are unable to use their prefrontal cortex to make decisions or think rationally; rather, they rely on habitual modes of being. This is known as the “Habit Circuitry”, or the software that has been created and shaped by experience and culture. A relevant example is how, over centuries of societal pressure, women have been socialized to be polite and pleasing. This cultural conditioning explains the tendency for survivors to say polite things or even smile during abuse, even when they are not consenting. During these moments, survivors are experiencing extreme fear, and their brains are operating on “auto-pilot” as a survival tactic. 

The last neurological impact of trauma is an effect on memory encoding. During a traumatic event, the brain does not encode memories in chronological order, which can lead to gaps in memory. These gaps are due to the selective tendencies of the brain’s “fear circuitry”. Whatever this ‘fear circuitry’ is focused on is more likely to remain encoded in a survivor’s memory. For example, a survivor may have a vivid recollection of the abuser’s shirt texture but not what time the abuse took place. This non-linear encoding system explains why it is difficult for many survivors to explain key details about their abuse; it may be because their brain’s survival mechanisms simply blocked it out of their memory. 

Myth v Fact – Misconceptions and Victim-Blaming Statements

Understanding the neurobiology of trauma can help dispel many myths and victim-blaming misconceptions surrounding sexual violence. The following statements are common myths that can be dispelled using clear neurobiological responses to trauma. 

Myth: If it was really an assault, they would have fought back. 

Neurobiology Fact: Disassociation, freezing, or losing body control are all survival reflexes driven by the brain’s “fear circuitry” that kicks in during moments of trauma or extreme fear. These experiences are known as “tonic immobility”, or when an individual is physically paralyzed by fear. This sense of mental and physical paralysis can inhibit a survivor’s ability to fight back or even move at all. Furthermore, during traumatic experiences, the prefrontal cortex becomes impaired. This impairment limits the survivor’s ability to logically think through the situation and craft a response.

Myth: Your story has changed over time. Why did you wait so long to tell anyone? You must be lying. 

Neurobiology Fact: During a traumatic situation, the brain’s fear circuitry causes memory encoding to function differently. Sometimes the brain may choose to encode seemingly unimportant details of an event rather than important information, such as what the perpetrator looked like or what they did. Additionally, these selected memories are not stored in chronological order. Thus, when survivors share their stories, they may seem scattered, but this is NOT a sign that the experience did not occur. In fact, it is a sign that the person’s brain has experienced trauma-induced survival mechanisms. It is also not uncommon for people who have experienced trauma to recall more information from the experience as time goes on. Research has shown that the brain is capable of preventing traumatic memories from coming to awareness as a coping mechanism. Typically, certain triggers recall or ‘recover’ the concealed memories. 

Myth: They continued interacting with the perpetrator afterward, so it must not have been assault.

Neurobiology Fact: After trauma, the brain may engage in “appeasement” or compliance behaviors to reduce perceived threat. This response is driven by survival instincts and fear conditioning, especially if the perpetrator is known to the survivor. Maintaining contact can be an unconscious attempt by the brain to regain a sense of safety or control, not an indication of consent or approval. 

Myth: They froze instead of escaping when they had the chance—why didn’t they just leave?

Neurobiology Fact: The freeze response is an automatic survival reaction regulated by the autonomic nervous system. When the brain determines that fighting or fleeing may increase danger, it can immobilize the body to avoid detection or further harm. Freezing is the most common reaction to trauma, rather than fighting back or running away. This response is involuntary and occurs without conscious choice, making escape neurologically inaccessible in the moment.

Trauma-Informed Care

Understanding the neurobiology of trauma can help promote trauma-informed care responses for victims of sexual abuse. Trauma-informed care, or TIC, is a holistic approach aimed at acknowledging the prevalence of trauma, evaluating the effects of trauma on survivors, taking steps to address the trauma, and empowering survivors by providing professional support. TIC is not a list of things to do but rather guiding principles for responders to help trauma survivors experience a sense of security and recovery after a traumatic experience. TIC is grounded in an understanding of the neurological impacts of trauma in order to emphasize victims’ physical, psychological, and emotional safety. TIC also has 5 core principles: safety, trust, choice, collaboration, and empowerment. So, how can you implement these core principles into your responses to aid survivors in a healthy healing?

1. Physical and emotional Safety

It is essential to provide survivors with a safe environment in which they feel welcome and comfortable. Ways to contribute to this sense of safety include active listening and mutual vulnerability. By listening in a nonjudgmental and engaged manner, survivors will know that their story matters and that this conversation is important to you. Additionally, one of the easiest ways to create a safe space for someone else is to share your own emotions, indicating that it is a safe space for feelings to be shared.

2. Choice and control

It is common for survivors of trauma to feel as though they no longer have a sense of control or choice. It is beneficial to demonstrate, through your actions, that the survivor can control the conversation and move at their own pace. This means avoiding unsolicited advice and asking “why?” questions. 

3. Collaboration

Sharing power can help survivors make informed decisions about their next steps on their journey. Providing information about available options, such as “I Have the Right To,” and reminding the survivor that they have the choice to make their next steps can offer helpful resources while reinforcing the sense of survivor independence. 

4. Trustworthiness

Survivors of trauma can feel like they don’t know who they can trust anymore or who is a “safe person”. Therefore, consistency is key. Continue to show up and check in on your friend or loved one. The process of recovery and healing looks different for everyone. They may feel pressure to “get over it.” Allow them time and space, and remind them they are not alone and that you will continue to be there for them.

Understanding the neurobiology of trauma reframes survivors’ responses as instinctive, protective brain processes rather than personal failures or choices. By recognizing how fear circuitry, memory disruption, and dissociation function during trauma, we can dismantle harmful myths, reduce stigma, and respond with empathy instead of judgment. This knowledge not only validates survivors’ experiences but also provides a critical foundation for trauma-informed care that prioritizes safety, empowerment, and healing.

Sources

https://noviolence.org.au/wp-content/uploads/2020/05/Trauma-Practice-Paper-FINAL-002.pdf https://www.safeaustin.org/supporting-survivors-a-trauma-informed-approach/