In her now-famous TED Talk, Dr. Nadine Burke Harris explains trauma as a nervous-system event.

A Nervous System Response

At its core, trauma is a nervous system event.

 If you find yourself in a situation that feels close enough to something deeply painful or life-threatening you experienced before, your brain might say, "Oh no. It’s happening again." 

That one thought is enough to trigger a cascade of physical and emotional responses.

This is why people with trauma often experience:

• Sudden panic or dread seemingly out of nowhere

• Emotional outbursts that don’t "match" the situation according to an outside observer

• Total shutdown, numbness, or detachment

• Intense reactions to people, words, or situations

Trauma creates a kind of time-loop in the brain. The past keeps hijacking the present.

Hypervigilance

One major symptom of trauma is hypervigilance—your brain constantly scans for threats, especially ones that resemble the original danger. 

You might:

• Always feel a bit "on edge"

• Have trouble sleeping or fully relaxing

• Notice every little shift in someone’s tone or body language

• Struggle to feel fully safe, even when nothing is obviously wrong

This nonstop scanning prevents you from fully letting your guard down. It also makes it harder to be your authentic self around others. Your brain is waiting for the other shoe to drop— even in moments where there is no other shoe.

Trauma Is Highly Situational

Trauma isn’t just defined by the facts of what happened, it’s defined by how it felt–how you felt. That means two people can go through the same terrible situation, and one might be traumatized while the other isn’t.

What matters is whether your nervous system was overwhelmed—whether the experience left you feeling helpless, frozen, or fractured.

And that’s not something you can talk yourself out of. Trauma doesn’t live in logic. It lives in the body.

Reenactment

Trauma lives in your body, so it also lives in your behavior. 

People who’ve experienced trauma often find themselves repeating dynamics or relationships that feel emotionally familiar, even if they’re harmful. This is called reenactment.

Reenactment is not a conscious choice. It’s the nervous system’s attempt to resolve an old wound by recreating it. It’s one of the ways trauma “haunts” or seems to follow you around. Unfortunately, this rarely leads to healing—it just keeps the cycle going. When trauma is unprocessed, your reactions will often feel like echoes of something deeper and older than the current moment.

Trauma is Everywhere and it’s Cumulative

Almost everyone has experienced something that could have left a lasting imprint on the nervous system. Relationship infidelity, a car accident, losing a loved one (pets included), disapproving parents, being the victim or perpetrator of a violent crime, etc.

Being exposed to multiple stressful or frightening experiences, especially without support, can make symptoms more severe and easier to identify. This is part of why trauma has historically been studied through the lens of military veterans and first responders: they are repeatedly exposed to obvious extreme situations.

But trauma doesn’t only come from war zones. 

Many people experience trauma in their homes, schools, relationships, or communities.

“Big T” and “Small t” Trauma

Big T traumatic experiences are graphic, shocking, and above all they are obvious: serious car accidents, natural disasters, sexual violence, witnessing death, or working in emergency services. These are often acute, external events that shock the system.

But there’s also little t trauma—the quieter wounds of childhood, emotional neglect, chaotic households, being bullied, or trying to make sense of confusing or frightening situations as a young person. These don’t always look dramatic from the outside, but they shape your nervous system in profound ways.

Little t trauma is often cumulative. A single moment may not register as traumatic, but over time, the emotional impact builds—especially if your environment lacked safety, support, or understanding.

Both kinds of trauma can result in:

• Lasting changes in how your body responds to stress

• Difficulty trusting others

• Emotional numbness or reactivity

• Intense, deep shame and guilt

Core Themes: Shame, Guilt, and Isolation

One of the most painful aspects of trauma is that it often leaves people feeling ashamed.

 You may believe it was your fault. You may feel broken, damaged, or unworthy. These beliefs aren’t true—but they are common.

Trauma is not a personal failure. 

It’s a sign that your body did its best to protect you, even if that protection now shows up in ways that feel confusing or destructive. Healing means learning to update those protective strategies so that they serve who you are now.

You are not alone. And you are not beyond repair.

Healing is possible. It begins with getting clear on what trauma really is and how it shows up in your life.