PTSD Explained

Post Traumatic Stress Disorder Explained

Post-Traumatic Stress Disorder (PTSD) is a condition that some people develop after experiencing or witnessing a traumatic life-threatening event or serious injury. Traumatic events can make us feel that our lives are unpredictable, that we are out of control, find it difficult to feel safe and trust other people, ourselves and our judgements. Our experiences often feel unfair, unjust, inhumane and cruel and can make us question our assumptions about the world and others. We can lose faith and become disconnected from others.

It’s normal to have these emotions, along with upsetting memories, feeling on edge, or have trouble sleeping after this type of event, but if symptoms last more than a few months and interfere with your day-to-day life, it may be PTSD. PTSD is a normal reaction to an abnormal situation.

It’s estimated that 50% of people will experience a trauma at some point in their life. The defining characteristic of a traumatic event is its capacity to provoke fear, helplessness, or horror in response to the threat of injury or death and therefore can affect anyone. Examples of traumatic events include assault, road traffic incident, natural disasters, domestic and child abuse, war, acts of terrorism and traumatic childbirth. (you can read more about the causes of PTSD here)

The majority of people exposed to traumatic events experience some short-term distress, but eventually, their trauma fades to a memory – painful, but not destructive. However, around 20% of people who experience a trauma go on to develop Post Traumatic Stress Disorder (PTSD). In the UK, that’s around 6,665,000 people, yet it is still an incredibly misunderstood, often misdiagnosed and stigmatized condition.

PTSD typically causes four different groups of symptoms: 

  • reliving the traumatic event perhaps in the form of flashback, nightmares or intrusive memories (also called re-experiencing or intrusion);
  • avoiding situations that are reminders of the event;
  • negative changes in beliefs and feelings;
  • and feeling hypervigilant and fearful to people and the world around you (also called hyperarousal).

There is a second, subtype of PTSD, called Complex PTSD, or C-PTSD. This is usually a result of repeated, or sustained traumas, and presents in a similar way to PTSD, but with some additional symptoms too. You can find out more about C-PTSD specifically here. For the purposes of the content on this page (and most of this website) when we talk about PTSD, we are also talking about C-PTSD too. 

“When you have PTSD, the world feels unsafe. You may have upsetting memories, feel on edge, or have trouble sleeping. You may also try to avoid things that remind you of your trauma — even things you used to enjoy.”

The hyperarousal that often comes with PTSD creates a disproportionate response to stimuli. For example, if snow was to fall of the roof of your home, a ‘typical’ response would be to jump or startle, and possibly look around. For someone with PTSD, their reaction is likely to be much more severe: jumping out of their seat, turning fully around, or hiding under a table heart pumping with fists clenched ready to meet an imagined threat.

Many PTSD sufferers also feel emotionally numb and have trouble communicating with others about the way they feel – this may make them more anxious and irritable.

Quite often, the feelings and symptoms of PTSD become so unmanageable and uncomfortable, that the sufferer starts to avoid anything linked to the original trauma which, as you can imagine, can affect day to day life.

Although there are many common symptoms of PTSD, it does not look the same in everyone. In addition, symptoms may come and go and may change over time from childhood to later adulthood.

‘PTSD is complicated by the fact that people with PTSD often develop additional disorders such as depression, substance abuse, problems of memory and cognition, and other problems of physical and mental health. The disorder is also associated with impairment of the person’s ability to function in social or family life, including occupational instability, marital problems and divorces, family discord, and difficulties in parenting.’

The good news is that there are effective treatments for PTSD and C-PTSD. Unfortunately, many people do not know that they have the condition or do not seek treatment due to stigmatisation, they don’t believe they can be helped, fear of discussing their trauma or not wanting to acknowledge their problems in coping.

“Getting better” means different things for different people.  For many people,  treatments such as EMDR and CBT can get rid of symptoms altogether. Others find they have fewer symptoms or feel that their symptoms are less intense. Your symptoms don’t have to interfere with your everyday activities, work, and relationships.

How is PTSD caused?

The human body is an incredible system, but it is also complex, and full of feedback loops between body parts and brain. If you interfere with any of these loops dramatically (as in the case of experiencing a trauma), you can affect the whole system.

PTSD is a psychiatric disorder that may occur in people who have experienced or witnessed a traumatic event – put simply, PTSD is essentially a memory filing error caused by the brain ‘suspending’ normal function during a traumatic situation. It causes a huge variety of life-altering and intrusive symptoms and so PTSD can cause substantial distress and disruption of social and occupational functioning, causing major problems in relationships and jobs. Symptoms usually begin early, within 3 months of the traumatic incident, but sometimes they begin years afterward.

PTSD is as ancient as humankind and can occur in all people, of any ethnicity, nationality, gender, occupation or culture, and at any age.

If someone is exposed to an intensely fearful and traumatic situation, their body and mind ‘suspends’ normal operations and it copes as well as it can in order to survive. This might involve reactions such as ‘freezing to the spot’ or instead the opposite ‘flight away’ from the danger (it’s been recognised that there are 5 main reactions to trauma – fight, flight, freeze, fawn and flop).

Your exposure to traumatic event can happen in one or more of these ways:

  • You experienced the traumatic event
  • You witnessed, in person, the traumatic event
  • You learned someone close to you experienced or was threatened by the traumatic event
  • You are repeatedly exposed to graphic details of traumatic events (for example, if you are a first responder to the scene of traumatic events)

Until the danger passes, many systems in the body are put on hold or adapted: your digestive system pauses, your muscles may tense up to be ready to flee or fight, your heart rate will increase, pupils dilate, and the ‘unimportant’ task of memory creation is put on hold. This means that the mind does not produce a memory for this traumatic event in the ‘normal’ way.

Under normal/non-traumatic circumstances, when information comes into our memory system (from sensory input such as what we can see, hear, taste, and smell), it needs to be changed into a form that the system can cope with, so that it can be stored. If the encoding doesn’t take place due to a traumatic situation – the memory can’t be processed. Instead, it is stored randomly, in pieces, in a variety of places within the brain.

Eventually, when the mind presents the ‘memory’ of the trauma for ‘filing’, or it is triggered by a smell, a place, or a person etc, it does not recognise it as a memory. As it understands, ‘the brain is in the middle of the dangerous event – it is not ‘outside’ looking in at this event, and therefore the entire system is not easily subject to rational control.’ These flashbacks are incredibly distressing. Reliving the trauma as if it were happening RIGHT NOW. The elements such as the facts of what happened, the emotions associated with the trauma and the sensations touch, taste, sound, vision, movement, and smell can be presented by the mind as real time information. They may also present as nightmares, and intrusive unwanted memories.

These re-experiences and flashbacks are a result of the mind trying to file away the distressing memory, and understandably can be very unpleasant and frightening because they repeatedly expose the sufferer to the original trauma. This danger response also sets off other stress reactions in the body such as blood pressure and heart rate increasing, blood sugar is raised and digestion is affected. The body enters a state of hypervigilance so it is aware of other dangers around it, with increased startle responses.

Your body and mind are doing things they SHOULD do when presented with a threat. But your body is designed for this to be an immediate fix, for short term fix which allows the body to settle once the threat has been resolved. But with PTSD, it is almost perpetual. A prolonged, extreme or repetitive trauma can physically injure the brain. ‘The best analogy is that the amygdala stays in the alert state so long that it gets ‘stuck’ there. It keeps the body from operating a healthy combination of… systems’.

Your brain (hypothalamic-pituitary-adrenal (HPA) axis) is activated by the stressful stimuli, and the disruption that occurs with PTSD can be conceptualised as a kind of “false alarm”. This ‘dysfunction’ of the HPA system is thought to produce hippocampal damage manifested as impaired memory. Simply put, PTSD physiologically changes your brain. The amygdala is responsible for fear responses and fear conditioning. Exposure to trauma can activate the amygdala and related structures inappropriately resulting in hypervigilance and inappropriate fear responses. Additionally, the part of your brain which regulates inappropriate fear responses (the medial prefrontal cortex) is impaired in people with PTSD. You can find out more about the regions of the brain involved in memory processing that have been implicated (hippocampus, amygdala, and frontal cortex) here.

As the mind continues to try to repeatedly process the memory, and the brain keeps retriggering itself into ‘danger’ mode, the individual also finds that their levels of awareness might change. People can become find it difficult to control their emotions and suffer intense symptoms of anxiety. This can present itself as both physical; shortness of breath, tight muscles, profuse sweating and a racing heart, as well as emotional: feeling on edge, hypervigilance (looking out for signs of danger all the time), avoidance of reminders of the trauma or feeling panicky.

The brain is programmed to process memories, and so the more the individual avoids things like thinking about the trauma, the less likely is it that any memory processing will actually occur, and the more likely it is that further attempts at filing a memory will occur automatically. This ultimately leads to further nightmares, flashbacks and intrusive memories which lead on to further hyper-arousal and emotional numbing, and this in turn leads on to more avoidance and so on. This is how the symptoms clusters perpetuate themselves in a vicious cycle which can go on for years – and when it goes untreated, PTSD can last for decades.

‘The injury is real. The injury is physical. It is not mere confusions or misdirected thinking, or sign of a weak character. It most certainly is not a case of ‘Just get over it’. In some cases, PTSD symptoms can have a cumulative effect and can get worse rather than better over time, which is why some PTSD sufferers ‘manage’ for such a long time without help, but they then worsen over time and eventually the symptoms become unmanageable.

For treatment to be successful, information and memory processing must be completed. This is why therapies such as EMDR aimed at helping the individual to process and work through the traumatic material are extremely beneficial. For some people, treatment can get rid of PTSD altogether. For others, it can make symptoms less intense. Treatment also gives you the tools to manage symptoms so they don’t keep you from living your life.

The history of PTSD

‘Exposure to traumatic experiences has always been a part of the human condition. Attacks by saber tooth tigers or twenty-first century terrorists have likely led to similar psychological responses in survivors of such violence.’ notes Matthew J. Friedman, MD, PhD, Senior Advisor and former Executive Director, National Center for PTSD.

The term ‘Post Traumatic Stress Disorder’ was actually only introduced in the 1980s. even though it’s a condition that has been around for thousands of years. Much of the misunderstanding around PTSD is due to the various names it’s previous been given: ‘vent du boulet’ syndrome from the French Revolutionary and Napoleonic wars, ‘shell shock’ and ‘soldier’s heart’ during WWI, ‘war neurosis’ during WWII; and ‘combat stress reaction’ or ‘post-Vietnam syndrome’ during and after the Vietnam War. 

The first official documented case of ‘psychological distress’ was reported in 1900 BC, by an Egyptian physician who described a ‘hysterical reaction’ to trauma – although ‘chronic mental symptoms caused by sudden fright’ were reported in the account of the battle of Marathon by Herodotus, written in 440 BC.

Additionally, research by Hippocrates (4607-377 BC) described that ‘stress reactions’ such as ‘frightening battle dreams’ often result from trauma. Research by Sigmund Freud’s pupil, Kardiner, also described what later became recognised as PTSD symptoms. It’s even noted in classical literature, where Mercutio’s account of Queen Mab in Shakespeare’s Romeo and Juliet highlights frightening dreams in which they experience past battles.

The dawning of the industrial revolution and the development of steam-driven machinery were the causes of some of the first civilian man-made disasters and cases of PTSD outside the battlefield.  Survivors of railway disasters puzzled doctors at the time – the display of psychological symptoms could not be explained, so it led them to assume there were microscopic lesions in the brain or spine of the survivor, and so they were diagnosed with ‘railway brain’ and ‘railway spine. Notably, Charles Dickens was involved in a rail accident in 1865 and wrote about his symptoms of sleeplessness and anxiety as a result of the trauma in a letter discovered in 2017

The scene was so affecting when I helped in getting out the wounded and dead, that for a little while afterwards I felt shaken by the remembrance of it,” the letter reads. “But I had no personal injury whatsoever. My watch (which is curious) was more sensitive, physically, than I; for it was some few minutes ‘slow’ for some few weeks afterwards.

“Except that I cannot yet travel on a railway, at great speed, without having a disagreeable impression – against all reason – that the carriage is turning on one side, I have not the least inconvenience left.”

“No imagination can conceive the ruin of the carriages, or the extraordinary weights under which the people were lying, or the complications into which they were twisted up among iron and wood, and mud and water,” 

“But in writing these scanty words of recollection, I feel the shake and am obliged to stop.”

It was these railway accidents which eventually saw the term ‘traumatic neurosis’ being used by Hermann Oppenheim.

Research and understanding of PTSD improved (and continues to improve) and although the symptoms of PTSD have been recorded for millennia, it took more than a century for physicians to classify it as a disorder with a specific treatment. In 1980, “post-traumatic stress disorder” became a formal diagnosis in the DSM’s third edition. Twelve years later, it was also adopted in the World Health Organisation’s International Classification of Diseases.

Hello! Did you find this information useful?

Please consider supporting PTSD UK with a donation to enable us to provide more information & resources to help us to support everyone affected by PTSD, no matter the trauma that caused it


You’ll find up-to-date news, research and information here along with some great tips to ease your PTSD in our blog.

Morning Pages for PTSD & C-PTSD

Morning Pages for PTSD & C-PTSD In the quest for mental well-being, there are a number of various techniques and practices. We’ve written before how writing and journalling can be a therapeutic support for those facing challenges with Post Traumatic

Read More »

Ink and Insights

The PTSD UK Ink and Insight Project In our continued commitment to supporting people on their path to healing and recovery, PTSD UK is proud to introduce the Ink and Insight Project – a unique project designed to empower people

Read More »

Dealing with PTSD over the holidays

Dealing with PTSD over the holidays Post Traumatic Stress Disorder can cause a whole host of symptoms, which can affect every area of your life, and when this is paired with ‘expectations’ of how you should feel, it can become

Read More »

Guest Blog – Rod Aungier

The road less travelled and the role of Gestalt therapy – Guest Blog We’ve previously written about benefits of Gestalt Therapy for those with PTSD and C-PTSD. Rod’s personal story in this guest blog sheds light on the transformative power

Read More »

Dip a Day December Challenge

events | dip a day december PTSD UK’s Dip a Day December Challenge Sign up now PTSD UK’s Dip a day December The challenge It’s no secret that cold water swimming, cold water therapy, focusing on a challenge and simply

Read More »

Santa in the City Run

PTSD UK Spreads Christmas Cheer with Santa Run Join thousands of Santas on the 6th or 7th of December 2023 at 7:00 pm, in the heart of London for an unforgettable 4.3km festive fun run! Plus, every adult runner is

Read More »

Treatments for PTSD

It is possible for PTSD to be successfully treated many years after the traumatic event occurred, which means it is never too late to seek help. For some, the first step may be watchful waiting, then exploring therapeutic options such as individual or group therapy – but the main treatment options in the UK are psychological treatments such as Eye Movement Desensitisation Reprogramming (EMDR) and Cognitive Behavioural Therapy (CBT).

Traumatic events can be very difficult to come to terms with, but confronting and understanding your feelings and seeking professional help is often the only way of effectively treating PTSD. You can find out more in the links below, or here.