The nervous system, and being retraumatised by telling

There is a window of tolerance, a band of arousal within which a person can stay present and reflective, and trauma tends to narrow it. Telling the story while the body is outside that window does not process the memory; it can re-file it where the original experience is stored and teach the system that telling equals overwhelm. This is why stabilisation comes before disclosure in the phased approach, not as a clinical preference but as the response to a mechanism, and why rebuilding trust in the body's signals turns out to be much of the work.

Written and reviewed by Natalia Cajide, Registered Psychologist (AHPRA PSY0002474316). 6 min read. Published 7 June 2026. Last reviewed 7 June 2026. Next review 7 June 2027.

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The window of tolerance

One of the things that surprises people, when they come to therapy hoping to "tell the story and get it over with," is how often telling makes things worse for a while. The body activates, sleep gets worse, the days after the session feel rough. The intuition that telling should help, that the work of trauma therapy is to get the story out, is so widely shared that the experience of being retraumatised by telling can feel like a personal failure. It is not. It is a nervous system event.

What the nervous system is doing when it activates, shuts down, or refuses to stay present with the story is not a sign that you are doing it wrong. It is the system doing exactly what it learned to do, which is to protect you from being overwhelmed. The clinical task is to work within that, not against it.

The most useful clinical frame I can offer here is what Daniel Siegel calls the window of tolerance (Siegel, 1999). The model describes an optimal zone of autonomic arousal within which a person can be present, reflective, and engaged. Above the window is hyperarousal: increased heart rate, racing thoughts, fight-or-flight activation, the felt sense of "too much." Below the window is hypoarousal: numbness, dissociation, shutdown, the felt sense of "not here." Inside the window, processing is possible. Outside the window, in either direction, the system is in protection mode and processing is not possible.

The window of tolerance is a clinical model, not a validated neurobiological mechanism. It is a description of what people experience and what therapists track. It is useful precisely because it gives the body's responses a coherent shape. Hyperarousal and hypoarousal are not failures of will. They are the system saying that the current conditions are outside what it can hold while staying present.

What trauma does, often, is narrow the window. After a major or prolonged trauma, the zone in which a person can stay present and reflective shrinks. Things that would not have activated the system before now do. Things that would have been processable now produce shutdown. This is one of the legacies of trauma that is least visible to others but most central to the daily experience of the person carrying it.

The polyvagal frame and its limits

You will often hear the nervous system described using language drawn from polyvagal theory, developed by Stephen Porges. The polyvagal language is clinically resonant. It distinguishes between ventral vagal states (social, settled, connected), sympathetic states (mobilised, fight-or-flight), and dorsal vagal states (shutdown, collapse, dissociation). For many people, the polyvagal map provides a clear and felt-sense-accessible description of what their body is doing.

Two things need to be said about polyvagal theory, alongside the clinical usefulness. The first is that the core anatomical and physiological claims of polyvagal theory are actively contested in the peer-reviewed literature. A 2023 paper by Paul Grossman in Biological Psychology argued that, in his assessment, each of the basic physiological assumptions of polyvagal theory is open to refutation, and that several of the comparative-anatomy claims are not supported by the available evidence (Grossman, 2023). Stephen Porges has continued to defend the theory (Porges, 2022). The debate is live in the literature. It is not settled science.

The second is that this matters for how the framework is used. The polyvagal language can be a useful clinical heuristic, a way to give a felt-sense map to states the body is showing. It is not the underlying neurobiology proven. When a clinician describes your nervous system in polyvagal terms, they are using a clinically helpful model, not stating an established physiological fact. The window-of-tolerance frame holds up regardless of which theoretical model is used to describe the autonomic states.

Why telling can re-injure

Here is the mechanism. When a person tells a traumatic story while the body is outside the window of tolerance, three things happen at once.

The first is that the autonomic arousal goes up. The system reads the conditions as not safe, even though the room is safe, because the story itself is sending the system back into the original conditions. The body responds as it would have responded then.

The second is that processing capacity drops. Outside the window, the parts of the brain that integrate experience into coherent autobiographical memory are not operating at full capacity. Telling a story while outside the window often means the telling does not get filed where new information goes. It re-files in the same place the original experience is stored, with the same lack of integration.

The third is that the body learns, again, that telling produces this state. The system makes the conservative association: telling equals overwhelm. Future attempts to tell, even in safer conditions, may activate the same protective response.

This is what is meant by being retraumatised by disclosure. It is not metaphorical. It is the system doing exactly what it should do when the conditions for processing have not been met.

Why stabilisation comes first

The phased approach to trauma treatment, recommended in Australian and international guidelines, is not a clinical preference. It is the response to this mechanism. A combined study of research findings by Coventry and colleagues in 2020, examining complex trauma interventions, supported a multicomponent approach with stabilisation work alongside processing (Coventry et al., 2020). A more recent study of research findings published in 2026 directly comparing phased to non-phased approaches for Complex PTSD found that phased approaches produced better outcomes and lower drop-out rates than approaches that moved straight to processing (Tran et al., 2026).

The clinical reasoning is straightforward. Before the story is told, the window of tolerance needs to widen. Before the window widens, the person needs tools to recognise and shift their autonomic state. Before they have those tools, they need a relationship in which the body's signals are recognised and respected rather than overridden. Each of these is a stabilisation task. Each of them is what happens before the story is told, not in spite of needing to tell it.

Trusting the slower order

Trusting your nervous system after trauma is harder than it sounds, because the body's responses can feel embarrassing, inconvenient, or like evidence that something is wrong with you. The shutdown that arrives in a moment that is not, objectively, dangerous. The flood of activation when the rational mind knows the room is safe. The way the story will not come out, or comes out and brings days of fallout with it. None of these is evidence of personal failure. Each of them is the system doing its work.

What I would rather offer than a tidy instruction is a different relationship to those responses. Not because the responses are pleasant, but because they are information. The body has not made a mistake. The signals it is sending are the only honest record you have of whether the current conditions are conditions it can settle into. The story comes later, when the system can hold it, in conditions it can recognise as different from the original ones. That waiting is harder than it sounds, and the days when it feels like delay rather than work are part of what living through this looks like. The slow rebuilding of trust in your own signals is, on the whole, what the work turns out to be.

This content is general information only. It is not a substitute for individual psychological or medical advice. Reading this does not establish a therapeutic relationship with Equal Psychology or any of their clinicians.