Cognitive Model of PTSD
Ehlers & Clark (2000) · Post-traumatic stress disorder
Written by Tarun Vermani, Trainee Clinical Psychologist Last reviewed
Ehlers and Clark's cognitive model of PTSD (2000) explains persistence as a sense of current threat, produced by a trauma memory not yet placed in the past and by strongly negative readings of what happened and what came after.
Cognitive Model of PTSD
Ehlers & Clark (2000)
Trauma Memory
A trauma memory that is poorly elaborated and not fully integrated into the past — fragmented, disjointed and easily triggered. Strong perceptual priming and a 'here and now' quality mean reminders provoke vivid intrusions and flashbacks that feel current.
Negative Appraisals
Excessively negative appraisals of the trauma and its aftermath — of the event ('it was my fault'), of one's own reactions ('I'm falling apart'), of other people ('no one can be trusted') and of the future ('I'm permanently damaged', 'nowhere is safe').
Current Sense of Threat
A sense of serious, current threat — felt internally (the body braced for danger) and externally (the world seems dangerous). This is the central feature that the trauma memory and the negative appraisals combine to produce.
Emotional Responses
Strong emotions following from the appraisals — fear and anxiety, but also shame, guilt, anger, sadness and feeling let down, depending on how the event is interpreted.
Coping Strategies
Coping and control strategies meant to reduce the threat — avoidance of reminders, thought suppression, rumination, hypervigilance, safety behaviours and numbing (e.g. alcohol). These maintain PTSD by preventing change in the memory and appraisals, and by increasing symptoms directly.
The published model, shown for reference. Switch to “Blank” to see the empty template you complete with a client.
Understanding the model
After a frightening or traumatic event, it's normal to feel shaken for a while, and usually the memory settles over time. In PTSD, though, the memory stays raw and the past keeps breaking into the present. This model explains why.
Two things keep the trauma feeling current. First, the memory of what happened is stored in a jumbled, fragmented way, without a clear sense that it is over. So reminders can trigger vivid intrusions — images, sounds or flashbacks — that feel as if the danger is happening now.
Second, the mind makes very negative sense of the event and its aftermath — 'I'm not safe anywhere', 'it was my fault', 'I've changed for ever'. Together these create a constant sense of present threat, with fear, shame, anger or sadness, and a body on high alert.
Understandably, people try to cope by pushing the memory away, staying on guard, avoiding reminders, or going over the event again and again. These strategies bring short-term relief but keep the memory from updating and stop the frightening beliefs being challenged — so the sense of threat carries on.
Questions therapists ask about this model.
Frequently asked questions
What keeps PTSD going according to this model?
Two routes converge. The memory of the event is held in a fragmented way, without a clear sense that it is over, so reminders trigger intrusions that feel as though the danger were happening now. Alongside this, the event and its aftermath are appraised very negatively — about safety, about the self, about the future. Together these produce a sense of threat in the present, which is the feature the model puts at the centre.
Why do avoidance and rumination make things worse?
Because they work in the short term, which is exactly why they persist. Pushing the memory away, staying on guard, avoiding reminders and going over the event repeatedly all bring some relief or a sense of control. What they also do is keep the memory from being updated and leave the frightening appraisals unchallenged, so in this model they are maintaining factors rather than steps towards recovery.
Why does the model focus on persistence rather than on the event?
Most people are shaken after a frightening event and find that the memory settles over time. Ehlers and Clark (2000) set out to explain why, for some, it does not, and located the answer in how the memory is stored and in the meanings drawn from the event and its aftermath. Ehlers, Hackmann and Michael (2004) later looked more closely at intrusive re-experiencing itself. NICE NG116 is the guideline covering post-traumatic stress disorder.
Worksheets and reading for this model
Using this model in session — for therapists
How to introduce the model, guided-discovery questions, treatment targets and a behavioural experiment are available to signed-in therapists.
References
- Ehlers, A., & Clark, D. M. (2000). A cognitive model of posttraumatic stress disorder. Behaviour Research and Therapy, 38(4), 319–345.
- Ehlers, A., Hackmann, A., & Michael, T. (2004). Intrusive re-experiencing in post-traumatic stress disorder: Phenomenology, theory, and therapy. Memory, 12(4), 403–415.
- Ehlers, A., Clark, D. M., Hackmann, A., McManus, F., & Fennell, M. (2005). Cognitive therapy for post-traumatic stress disorder: Development and evaluation. Behaviour Research and Therapy, 43(4), 413–431.
This diagram is a reconstruction of the published model for clinical and educational use, grounded in the sources above.
Cite this page (APA 7)
Vermani, T. (2026). Cognitive Model of PTSD. Formulate. https://formulatetools.co.uk/tools/formulation/ptsd-ehlers-clark
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