Your 12-year-old is begging not to go to school because they have another headache. A few hours later, the school nurse calls to say it still hasn’t gone away. You pick them up, and by the end of the day, they seem totally fine.

This is the sixth time this month.

The pediatrician can’t find anything physically wrong. You’re running out of PTO, and deep down, you know your tween isn’t making it up.

So what’s going on?

When a nervous system has been through trauma, the signs aren’t always what you’d expect. Physical symptoms like headaches and stomachaches can be the body’s way of communicating what words can’t express.

Trauma doesn’t just live in our thoughts. It’s stored in the body, too.

What Happens in the Nervous System After Trauma

The brain, nervous system, and body don’t work in isolation. They function as one deeply connected system. Think of them like a set of piano keys. When one key sticks or falls out of tune, the entire melody feels off. The same happens in our bodies. When the nervous system becomes overwhelmed or dysregulated, it impacts how we feel, think, and respond.

This nervous system imbalance is often what’s behind the emotional and physical reactions we see in tweens and teens after trauma.

Our nervous system moves between three main states to help us stay regulated and responsive to what’s happening around us. These states are designed to keep us safe, and we shift between them all the time.

The Nervous System’s Three Main States

Parasympathetic State: Rest and Digest

This is our calm, regulated state. When the nervous system is in a parasympathetic state, the body feels safe. Heart rate and breathing slow down and digestion works properly.

In this state, kids are more likely to feel connected, relaxed, and focused. This is where learning happens, relationships feel good, and the world doesn’t feel like a threat.

Sympathetic State: Fight, Flight, or Freeze

This is the brain’s built-in alarm system. When it senses a threat, the brain sends a message to the body to gear up. Pupils narrow, breathing speeds up, and the heart races.

Digestion slows, muscles tense, and body temperature rises as the body prepares to act. Our brain and body go on high alert to protect us. For a tween or teen with unresolved trauma, the brain and body might stay in this state much longer than they should.

Dorsal Vagal State: Shutdown

When the brain perceives something as too overwhelming or inescapable, it shifts into shutdown. This is the body’s survival response to extreme stress.

Heart rate and breathing slow down, body temperature lowers, and the body conserves energy. Kids and teens in this state might feel numb, tired, foggy, disconnected, or like they’ve checked out. It can look like zoning out, low energy, depression, or a sense of helplessness.

All three states are part of a healthy nervous system. Our bodies are designed to move between them throughout the day.

A burst of stress before a test (sympathetic) can help sharpen focus. Hanging out with friends (parasympathetic) helps restore balance. Scrolling on the phone in bed might be a sign of moving into shutdown.

When trauma is stored in the nervous system, it can disrupt these natural shifts. Some kids stay stuck in high-alert mode. Others may shut down, sometimes without warning. Recognizing these patterns helps us understand that what looks like “behavior problems” is often the nervous system’s way of trying to stay safe.

When the Body Says “Not Safe” Even if the Mind Disagrees

When kids experience trauma, their nervous system becomes dysregulated and more sensitive to cues of threat. Sometimes those cues are obvious, like hearing raised voices or seeing something scary on TV. Other times, they’re subtle and hard to name, but the body still responds like there’s danger.

This is where two important processes come in: interoception and exteroception.

Interoception: The Internal Radar

Interoception is the ability to sense what’s happening inside your body. Hunger, thirst, temperature, heart rate, nausea, and fatigue are all internal messages letting you know how you’re doing.

Kids and teens who have experienced trauma may have an overactive or underactive interoceptive system. For example, a teen might notice their heart racing and immediately feel like something bad is about to happen. That same rapid heartbeat may have been present during their trauma, so the body reacts as if it’s a sign of threat, even when nothing harmful is happening.

Because trauma changes how safe the body feels, even harmless sensations like butterflies in the stomach before a big test can be misunderstood as a warning. When that happens, the nervous system sounds the alarm and shifts into a stress response, even if everything around them is calm and safe.

Exteroception: Sensing the Outside World

Exteroception is the way we take in information from our surroundings through our senses such as sights, sounds, smells, and touch.

For tweens and teens who have experienced trauma, this system can become extra sensitive. A slammed locker, a sharp tone of voice, or a familiar smell might set off a strong physical reaction, even when your tween or teen knows they’re safe.

These reactions happen because the body is working to protect them. The nervous system may link certain sights, sounds, or smells to a past experience and respond as if that moment is happening again.

This is why trauma responses can feel sudden and confusing. A teen might go from calm to irritable or withdrawn within seconds, without fully understanding why. While it might seem out of proportion to the moment, for their nervous system, it feels like the right and necessary response.

Why Trauma Shows Up in the Body

Trauma in kids and teens happens when their brain and body do not feel safe, so they shift into survival mode. Sometimes, even long after the danger has passed, the nervous system keeps operating in that same mode, focused on staying protected above everything else.

When the nervous system stays on high alert or shuts down for too long, it often shows up as physical symptoms. Because young brains and nervous systems are still developing, tweens and teens are especially sensitive to this kind of body-based stress response.

Common physical signs of trauma in kids and teens may include:

Headaches
Stomachaches
Nausea
Increased or decreased appetite
Bathroom troubles (constipation, diarrhea)
Muscle tension
Unexplained aches or pains
Racing heart
Sensitivity to noise

These symptoms are not “in their head.” They are the body’s way of saying, “I’m not OK.”

While they can be signs of trauma stored in the body, it’s still important to consult a pediatrician or medical provider to rule out medical causes.

Sometimes the brain blocks out parts or even all of a traumatic memory. This often happens in early childhood or during moments when the nervous system sensed an extreme threat. In those situations, the brain may temporarily shut down memory functions as a way to help the body survive. Even if the story itself isn’t accessible, the body can hold on to it. Sensations, symptoms, and emotional reactions that appear later are often the body’s way of carrying what was too much to process at the time.

How EMDR Helps Tweens and Teens Heal from Trauma

Because trauma affects the brain, body, and nervous system, therapy needs to include all three areas to be truly effective. This doesn’t mean diving into every detail of what happened. It means working in a way that’s gentle, attuned, and paced to what the child is ready for.

Therapy might involve building body-based awareness, learning how to shift into a calmer state, or noticing how emotions show up physically. It can also include expressive approaches like art, music, or play-based techniques that support safety and connection. These aren’t extra steps. They’re essential for helping the nervous system feel grounded and safe again.

In my work, one of the primary tools I use is EMDR therapy. EMDR (Eye Movement Desensitization and Reprocessing) is an evidence-based approach that uses bilateral stimulation, such as tapping or guided eye movements, to help the brain reprocess painful experiences. It doesn’t require retelling the full story. Instead, it helps the brain and body work together to resolve what happened, even when the conscious mind doesn’t have all the details.

EMDR has been shown to help reduce symptoms such as anxiety, panic attacks, sleep difficulties, irritability, and physical symptoms tied to trauma. It offers tweens and teens a secure, supportive space where real healing can take place.

Healing the Brain, Body, and Nervous System Supports Growth

Healing goes beyond symptom relief. It creates space for growth, connection, and confidence. Trauma can disrupt focus, relationships, emotional regulation, and self-esteem. With the right support, those areas can begin to mend.

As the nervous system becomes more regulated, behaviors and symptoms often start to shift. The tween who once cried before school might begin connecting with friends. The teen who struggled with headaches may feel less tension and more in control. Their body and mind begin to feel safe again.

When tweens and teens heal from trauma, they can move from simply surviving to truly thriving. They learn to trust their inner cues, connect more freely with others, and build a future not defined by the past. Their body becomes a safer place to live.

That 12-year-old who used to beg to stay home with another headache might still have hard days. But with the right trauma therapy, those headaches begin to ease. They start to understand what their body is telling them, and instead of responding with fear, they learn to respond with curiosity, self-compassion, and care.

If your tween or teen lives in Pennsylvania or Delaware and is struggling with the effects of trauma, I invite you to schedule a free 15-minute phone consultation. Together, we can explore whether trauma therapy might be the right next step for their healing.

Important: This post is for informational and educational purposes only. This post should not be taken as therapy or medical advice or used as a substitute for such. You should always speak to your own therapist before implementing this information on your own. Thank you!

Understanding the Mind-Body Connection in Kids and Teens: Headaches, Shutdown, and the Hidden Signs of Trauma