Post-traumatic stress disorder (PTSD)

This information is for anyone who is experiencing post-traumatic stress disorder (PTSD), or who knows someone who is.

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There are several possible explanations for what causes PTSD.

Psychological

The psychological symptoms of PTSD are deeply unpleasant and distressing. However, these symptoms can make sense when we think about how our minds might work to protect us after a traumatic event.

  • Memory – After experiencing a traumatic event we might be unable or unwilling to remember it. Although it can be distressing to remember what has happened, doing so can help us to make sense of the event. This can be helpful for our mental health.
  • Intrusive thoughts or flashbacks – These can be seen as replays of what happened. They might force us to think about what has happened so we might be better prepared if it were to happen again. However, in PTSD these thoughts just cause us to feel distressed.
  • Avoidance and numbing – It is tiring and distressing to remember a trauma. Avoidance and numbing can help you to stop thinking about what happened. However, they also stop you from making sense of your experiences.
  • Hypervigilance – If we are ‘on guard’, we might feel prepared to react quickly if another crisis happens. It can also give us the energy for the work that’s needed after an accident or crisis. However, it can also be exhausting and prevent us from doing things we used to enjoy.

Physical

Some of the physical symptoms that occur with PTSD occur because our bodies are trying to incorrectly process trauma.

  • Adrenaline – This is a hormone our bodies produce when we are under stress. It helps to prepare our bodies for activities that need a lot of energy, for example, running or fighting someone off. When the stress disappears, the level of adrenaline should go back to normal. In PTSD, vivid memories of the stressful event can keep the levels of adrenaline high. High levels of adrenaline can make you tense, irritable and unable to relax or sleep well.
  • The hippocampus – This is a part of the brain that processes memories. High levels of stress hormones, like adrenaline, can stop it from working properly. This means that memories of the traumatic event aren’t processed. This can cause you to remember the event as though the risk is still present, rather than seeing it as something that happened in the past. 

Published: Nov 2021

© Royal College of Psychiatrists