What Is Developmental Trauma?
It Can Affect You Long After Childhood
When we think about trauma, most people picture a specific event—something sudden, overwhelming, and memorable. But trauma doesn’t always work that way. In fact, some of the deepest wounds come from what didn’t happen: the care we didn’t receive, the safety that wasn’t there, the connection that never came.
This kind of trauma—developmental trauma—happens in the early years, when our brains and bodies are still wiring themselves. And even if we can’t remember those early experiences, they shape us all the same.
Brains Grow from the Bottom Up
Our brains don’t start fully built. They develop in stages, from the bottom up—starting with the most basic survival functions and moving toward higher-level thinking, emotional regulation, and connection.
Here’s the general order:
Brainstem: Regulates basic functions like heart rate and breathing.
Midbrain (Limbic System): Processes emotions, threat, attachment, and memory.
Cortex: Handles reasoning, self-awareness, language, and impulse control.
Each level of the brain builds on the one before it. If trauma happens early—especially during those bottom-floor phases—it disrupts the whole foundation.
The First Year: A Critical Window
The first year of life is one of the most intense periods of brain development we ever go through. At birth, a baby’s brain is about 25% the size of an adult’s, and by age three, it reaches about 80%. That early growth is explosive—and profoundly shaped by experience.
In infancy, a child’s brain forms millions of new neural connections every second. But it doesn’t keep them all. The brain strengthens the pathways that are used and starts pruning the ones that aren’t.
This process is called synaptic pruning. Think of it like sculpting—removing the extra so what’s left becomes more efficient, refined, and specialized.
When a baby’s environment is safe, predictable, and nurturing, the brain prunes wisely. But in environments with high stress, trauma, neglect, or fear, the brain might:
Strengthen stress-related pathways (like hypervigilance)
Prune away connections involved in emotional regulation, connection, and curiosity
Over-develop parts of the brain responsible for threat detection (like the amygdala)
In other words, the brain adapts for survival, not for thriving.
How Relationships Shape the Nervous System
One of the most powerful things shaping the brain in those early years is the caregiver's nervous system. A baby’s developing nervous system is built through co-regulation—they learn how to calm down by being calmed down. Their sense of safety is built by being kept safe. And their ability to self-regulate is literally wired through repeated experiences of external regulation.
Caregivers who are:
Responsive (they notice and respond to the child’s needs)
Predictable (they show up in mostly consistent ways)
Emotionally regulated themselves (or at least able to repair when they aren’t)
…help build a nervous system that can handle stress, stay grounded in relationships, and recover after emotional upheaval.
This isn’t about being perfect. It’s about being attuned—noticing what the child is communicating and making an effort to meet them there. And when things go awry (as they always do), it’s about repair.
Rupture and Repair
In any relationship, there will be moments of rupture—misattunement, frustration, disconnection. What matters most is whether repair happens. For kids, repair teaches:
That conflict doesn’t mean abandonment
That emotions don’t have to be handled alone
That relationships can survive hard moments
When rupture is frequent and repair is missing, that’s when attachment injuries happen. And over time, those injuries shape how we relate to others—and to ourselves. Watch the Still Face Experiment to see it in real time:
Attachment Shapes Everything
Attachment is the nervous system’s blueprint for relationships. It forms through repeated emotional experiences with early caregivers—not just what they say, but how they respond to our needs, our emotions, our distress.
When those responses are warm, predictable, and attuned, we build a secure attachment. We learn:
That relationships are safe
That comfort is available
That we are worthy of care and connection
But when those early relationships are chaotic, distant, or frightening, different patterns can form.
Common Insecure Attachment Styles
Anxious (Preoccupied) Attachment
Develops when caregivers are inconsistent—sometimes attentive, sometimes unavailable. The child learns to stay hyper-aware of others' moods, fearing abandonment. Love may feel unpredictable or unstable, so they cling hard to connection.Avoidant (Dismissive) Attachment
Develops when caregivers are emotionally distant or discourage emotional expression. The child learns not to depend on others or express needs. They may grow up highly independent but disconnected from their own emotional needs and uncomfortable with vulnerability.Disorganized Attachment
Develops when caregivers are frightening, frightened, or chaotic—when the child’s source of comfort is also a source of fear. This creates deep internal conflict: the child wants closeness but is also terrified of it. This often shows up later as unpredictable behavior, difficulty trusting others, or feeling unsafe even in safe situations.
These attachment styles aren’t conscious choices. They’re adaptations—strategies the nervous system develops to stay safe in an unsafe or inconsistent environment.
Abuse vs. Neglect: The Wounds We Don’t See
We often recognize trauma when it’s obvious—physical abuse, sexual violence, verbal cruelty. But neglect is just as harmful, sometimes more so, because it’s invisible. It’s hard to name what you didn’t get.
No one responded to your cries.
No one soothed you when you were scared.
No one delighted in you just because you existed.
It’s incredibly difficult to give someone what they never received. There’s no template, no memory, no “how-to” guide already stored in the nervous system. That’s why people with developmental trauma often don’t know why they’re struggling. The injury is so early, it’s disconnected from conscious memory.
“But They Won’t Remember…”
This is a common belief. And it’s true—young children don’t form explicit (conscious) memories of early trauma.
But trauma is stored in the body, not just the mind. And what they do have is implicit memory: the nonverbal, body-based memory of what happened, or more accurately, how it felt.
So even if a child can't tell you what happened, their nervous system can. You might see it in:
Emotional reactivity
Shutdowns or dissociation
Sensory sensitivities
Aggression or withdrawal
Delays in emotional regulation
Their behaviors may not make logical sense, but their body remembers.
There’s Still Room to Grow
The good news? The brain is still building itself for years—especially in childhood, but even into young adulthood.
When a child missed out on early connection, some of that can be recreated later in intentional, developmentally-informed ways. For example:
Rocking an older child who was neglected as an infant can help regulate their nervous system. The rhythmic motion of rocking mimics the heartbeat and builds the internal sense of rhythm that supports walking, balance, and emotional regulation.
Predictability, co-regulation, and warm attunement—even if they come later—can begin to fill in the gaps of what was missed.
Movement, rhythm, music, touch, and deep connection can all help rewire the nervous system over time.
Repair doesn’t mean the trauma didn’t happen. It means the blueprint is still being revised.
Moving Forward (Even If It's Messy)
Developmental trauma is real, and it runs deep. But it doesn’t mean a person is broken or beyond healing. It means their nervous system adapted to survive something it never should’ve had to.
Healing doesn’t always look like big transformations. Sometimes it looks like learning to pause. Learning to feel safe being seen. Letting someone close and not running away (literally or emotionally). Learning to be kind to yourself in places where there used to only be shame.
It’s not always clean or linear. But healing is possible.
And if this resonates with you, it might mean that what you’re struggling with now didn’t start with who you are—but with what happened to you.
And that means you don’t have to stay stuck in it forever.
