You are halfway down the cereal aisle with a list in your hand and three things still to find.
The lights are too bright, someone behind you is having a loud phone conversation, and you have just realised the brand you wanted has moved. Something in your chest tightens. You cannot quite remember what you came in for.
Most of us have had a version of this moment, but for autistic and ADHD people, and for many who live with anxiety or trauma, it can happen several times a day. Polyvagal theory is one of the most practical frameworks for understanding why.
What is polyvagal theory?
Polyvagal theory is a model of the nervous system developed by the American psychologist Stephen Porges.
It has become widely used in trauma-informed counselling, therapy and wellbeing practice, and it offers a useful map for understanding why the body reacts the way it does to everyday situations.
The central idea is straightforward. Your nervous system is continually scanning your environment for cues of safety or danger, and depending on what it picks up, it shifts you into one of three states. These states are not choices you make consciously, they are physiological responses that happen below the level of thought.
It is worth noting that some of the original neurological claims behind polyvagal theory remain a topic of scientific debate. That said, as a clinical and practical framework for understanding nervous system states, it has proved enormously useful to therapists and the people they work with.
The three zones of your nervous system
Many counsellors describe the polyvagal states as a traffic light: green, yellow and red.
Green zone: safety and connection
In the green zone, your nervous system feels safe. You can think clearly, connect with other people, take in new information and respond to challenges with flexibility. Your breathing is steady, your heart rate is settled, and your body is open to the world.
This is where most of us would like to spend most of our day. It is also where you do your best learning, your warmest conversations and your most creative work.
Yellow zone: fight or flight
When your nervous system picks up a threat, real or perceived, it shifts into the yellow zone. This is the classic fight-or-flight response: heart rate climbs, muscles tense, attention narrows.
In the yellow zone, you might feel frustrated, irritable, anxious or restless. The body is mobilising for action. A driver cutting you off, a difficult email, an unexpected meeting request can all tip you here within seconds.
The yellow zone is not bad in itself. It is your nervous system doing its job. The problem comes when you stay there too long, or when small triggers keep pushing you back in.
Red zone: shutdown and freeze
If the threat feels too big to fight or flee, your nervous system can shift again, this time into the red zone. This is the freeze state: a kind of internal shutdown that can feel like numbness, hopelessness or exhaustion. You may feel unable to face simple tasks, reluctant to open emails or answer the phone, and quietly cut off from the people around you.
The red zone is often misunderstood. It is not laziness or low motivation. The body is conserving energy because it has decided the situation is too much to manage actively. Recognising it for what it is can be the start of getting out of it.
How your body responds in each zone
The differences between the three zones are not just psychological, they are deeply physical.
In the red zone, your heart rate and blood pressure drop, your digestion slows, your facial expressions flatten, and the body releases chemicals that act as natural painkillers and prepare you for a long period of inactivity.
When you begin to move back towards the green zone, the picture reverses. Digestion picks up, resistance to infection improves, your face becomes more expressive, and you become more open to rest, recovery and connection with the people around you.
For autistic and ADHD people, who often experience sensory overwhelm and emotional dysregulation more intensely, understanding these physical patterns can be genuinely useful. Recognising that your body has shifted states, rather than that something is fundamentally wrong with you, often takes some of the shame out of the experience.
Why this matters for neurodivergent people
If you live with ADHD, autism or related differences, your nervous system may be more sensitive to environmental cues than the average. Lights, noise, transitions, social demands and unexpected change can all push you into the yellow or red zones more quickly than they would for a neurotypical person.
This is not a weakness, and it is not an exaggeration. It is a different baseline of nervous system reactivity, and once you understand it, you can start to work with it rather than against it.
Practical tools to stay in the green zone
The most useful insight in polyvagal theory is also the most actionable: you can learn to notice the moment your nervous system starts moving into the yellow zone, before it tips into red. Once you can see the early signs, you have choices.
In the supermarket example, that might mean stopping for a minute in the cereal aisle, breathing slowly, taking a sip of water and giving the nervous system a moment to settle. It looks like a small thing. It is. Small things, done regularly, are what keep the system in the green zone.
Other practices that support the green zone include:
- Slow, steady breathing, particularly with longer exhales than inhales
- Gentle movement and time outdoors
- Connection with people who feel safe, even briefly
- Familiar music, comforting routines and sensory anchors
- Naming what you are feeling, out loud or in writing
The five-minute joy practice
A simple practice many counsellors recommend is this: every day, find five minutes of something that brings you genuine joy. Not productive, not improving, not useful. Just joy.
The point is not escapism. It is that the nervous system needs regular reminders that safety, pleasure and connection are still available. Over time, those small moments build up, and the green zone becomes the place you live in most often, rather than the place you visit on good days.
If sensory overwhelm, shutdown or emotional dysregulation are persistent features of your daily life, it may be worth talking to a clinician about whether ADHD, autism or another underlying difference is part of the picture. Understanding the why often unlocks better tools for the how.
This article is based on a conversation with Ruth, a person-centred counsellor at Health is One, exploring how polyvagal theory shows up in everyday life. Watch the full conversation above.
