Safety first: how a child’s nervous system shapes behaviour, connection and learning
When we meet a child for the first time, we often start with the visible things. Perhaps they are refusing school, melting down in the evenings, avoiding homework, or struggling with daily routines. As parents and professionals, we are used to asking questions like, “What are they doing?” and “How do we change it?”
Polyvagal theory invites us to add a quieter but crucial question underneath: “How safe does this child’s body feel most of the time?”
According to polyvagal theory, every nervous system spends the day scanning for cues of safety and danger. This scanning is called neuroception. It is not logical and it is not conscious. A child does not wake up and decide, “I will feel threatened by the classroom lights today.” Their body simply takes in a thousand small signals – facial expressions, noise levels, routines, smells, touch, past memories – and makes a snap judgement: safe enough, or not.
When things register as “safe enough,” the nervous system leans into what is called the ventral vagal state. In this state, the child is more able to use their “social engagement system.” Their face is more animated. Their voice has more melody. They can look towards people instead of away. Their thinking brain is more available. In attachment language, this is the state that supports a secure base: the child feels able to explore, come back, seek help and try again.
This is also the state where occupational therapists see the richest participation. Children can join games, follow a simple instruction, try a new skill and cope with small frustrations. It does not mean they are perfectly calm or that everything is easy. It simply means their system is steady enough that learning and connection are possible.
When the body leans towards threat, the pattern looks different. One common response is a fight–flight state. Here the sympathetic nervous system steps in. Heart rate and breathing increase, muscles tense, and the body prepares for action. On the outside, you might see a child who is argumentative, restless, silly in a way that feels “too much,” impulsive, or quick to shout or storm off. In some children, especially those with ADHD or sensory‑seeking profiles, this can be mistaken for deliberate misbehaviour when it is largely a state shift.
The other major pattern is a shutdown or dorsal vagal state. This is the body’s “I am done” response. It conserves energy and blunts emotional impact. From the outside, shutdown can look like apathy: a child who shrugs, stares at the desk, says “I don’t care,” or refuses to start tasks. In reality, their system may be overwhelmed and out of resources.
These three patterns map neatly onto the window of tolerance idea that many families learn from psychologists. Inside the window, a child can think, feel and act flexibly. Above the window is hyper‑arousal (fight–flight). Below the window is hypo‑arousal (shutdown). The important thing to remember is that the size of the window is not fixed. It can be widened or narrowed by past experiences, current stress, sensory differences, health issues, sleep, and the quality of relationships around the child.
This is where OT, polyvagal theory and attachment theory all overlap. Children with a history of medical trauma, bullying, unstable housing, or other significant stressors often have nervous systems that are understandably cautious. Similarly, autistic children, children with ADHD or anxiety, and children with sensory processing differences may experience ordinary settings (classrooms, shopping centres, playgrounds) as more intense or unpredictable than adults realise.
As occupational therapists, we are not just looking at what the child does. We are asking:
What does their nervous system have to deal with each day?
How wide is their window of tolerance right now?
Which relationships help them feel safer?
Which environments repeatedly push them into protect or collapse states?
Once we understand the state story, the intervention story changes. Instead of simply adding more strategies or more rewards, we work with families and teachers to create more “ventral vagal moments”: times and places where the body can experience “safe enough.”
That can be as simple as slowing the morning routine so there is time for breakfast and a short connection ritual, instead of rushing out the door in a state of panic five days a week. It might mean adjusting how instructions are given in the classroom – one step at a time, with visual support – so the child does not spend the whole day bracing for the next demand. It might involve sensory changes: softer lighting, fewer visual distractions, noise‑reducing headphones, or access to movement.
In more formal OT language, we might talk about using the Person–Environment–Occupation (PEO) model. The person is the child and their nervous system, history, preferences and strengths. The environment is the physical space, the social setting and the routines. The occupation is whatever they are trying to do – attend school, play sport, get dressed, eat a meal, participate in therapy. Polyvagal theory gives us more detail about the “person” and “environment” pieces, so that we can shape the occupation in a way that respects their state.
We are not lowering our expectations of the child’s potential. We are choosing to line up expectations with biology. When we ask a child to learn new skills, manage big feelings and meet demands from a place of relative safety, they have a far better chance of succeeding – and of feeling good about themselves while they do it.