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What is post traumatic stress disorder?

How do people react when something terrible happens? Everyone has their own way of responding to life-threatening or unexpected experiences - you might feel afraid and overwhelmed while a friend who goes through the same thing might feel shocked and grateful to be alive. These thoughts and feelings can be intense and difficult to manage, but for most of us our reactions to traumatic events are completely normal, temporary, and fade over time.
If a person has trouble recovering and their feelings about the experience remain present or worsen as time passes, they may have a mental illness called Post Traumatic Stress Disorder (PTSD). Post traumatic stress disorder is an extreme reaction to trauma that can change how a person thinks, feels, and behaves and causes considerable distress or affects their ability to function.

How are things supposed to work normally?

As you have new experiences in life, your brain has to make decisions about whether or not the situation is stressful or dangerous. If your brain perceives something as life threatening, it activates an immediate emergency response throughout your body. This response, called fight or flight, puts your body on high alert and releases hormones like adrenaline and norepinephrine. Fight or flight increases your chance of survival by shifting your body’s focus and effort to managing the stressful situation. When your safety isn't at risk any more and the threat is gone, your brain shuts down stress responses and you are able to return to normal.

What happens when things go wrong?

Sometimes when you have an experience that is extremely terrifying or chronically stressful, your brain overestimates how much danger you're in and your stress systems malfunction. Instead of returning to normal over time, your body stays on high alert and keeps releasing stress hormones. When this happens, different areas of your brain start to make mistakes as they interpret the world around you and tell the rest of your body how to respond. Post traumatic stress disorder is associated with problems with brain structures and neurotransmitters (the brain’s chemical messengers) that usually manage how you respond to fear and stress.
Normal functionPost traumatic stress disorder
AmygdalaSets off fight or flight in response to dangerSets off fight or flight in response to memories or thoughts about danger
HippocampusTransfers and stores information into memoriesStores memories incorrectly and affects memory retrieval
Prefrontal cortexComplex thinking, decision making and appropriate behaviorDysfunctional thought processes and decision making; inappropriate responses to situations
Hypothalamus-pituitary-adrenal (HPA) axisReleases hormones like cortisol to help manage and direct efforts to stressorOveractive, which leads to imbalances in hormone levels and increases stress and anxiety


There are four main symptoms of post traumatic stress disorder that develop after traumatic experiences. These symptoms last at least one month and include:
  • reliving the event: repeatedly re-experiencing the trauma in the form of nightmares or upsetting dreams, flashbacks, and uncontrollable thoughts. When this happens, the body often reacts by activating fight or flight.
  • avoidance: person avoids anything related to trauma. This includes avoiding situations that could trigger flashbacks or uncontrollable thoughts, avoiding places, people, and activities that remind them of what happened to them, and suppressing feelings or thoughts about the trauma.
  • hyperarousal: heightened physiological arousal and increased reactivity to stress and trauma. People with hyperarousal may be jittery and are startled easily. They often have problems with concentration because they’re constantly alert and looking for danger. Hyperarousal often leads to irritability and trouble sleeping.
  • changes in thoughts, feelings and beliefs, like:
feeling sad, anxious, or afraid most of the time
becoming emotionally numb
losing interest in activities and relationships
thinking of themselves as a bad or guilty person
believing that the world is a scary, dangerous place and people can’t be trusted
The symptoms of post traumatic stress disorder are often debilitating and interfere with the person’s ability to work, go to school, and have meaningful relationships. If left untreated, they can become so severe that the person attempts suicide.

What causes post traumatic stress disorder?

Post traumatic stress disorder is caused by exposure to an extremely stressful or traumatic event that is dangerous and life-threatening for you or someone you care about, which you witness or live through, like:
  • military combat
  • violent crimes and physical assaults
  • natural disasters like tornadoes, floods, and earthquakes
  • serious accidents like house fires or car crashes
  • rape and sexual assault
There is a dose-response relationship between trauma and post traumatic stress disorder, which means that severity, duration, and proximity of exposure to trauma can affect whether or not you develop symptoms. So, if you personally experience chronic, severe trauma like childhood sexual abuse or war, you are more likely to have symptoms than a person who witnesses one car accident. Other risk factors include:
  • Personality: borderline, antisocial, dependent, and paranoid personality traits are associated with post traumatic stress disorder. People with these characteristics tend to be emotionally reactive and agitated in stressful situations and take longer to recover from negative experiences.
  • Perceived control: if you have an external locus of control you believe that you don’t have power over the things that happen to you, which can make it harder for you to cope with stress and increase your vulnerability after trauma.
  • Social support: if you don’t have a strong family or peer support system, or did not as a child, you are much more likely to develop post traumatic stress disorder.
  • Mental illness: if you have a history of depression, anxiety, bipolar disorder, or substance abuse, or if you have a close relative with depression you are more likely to develop post traumatic stress disorder after a traumatic event.
  • Life events: stressful life events like death in the family, divorce, or losing your job can affect how you experience trauma and increase your risk of developing post traumatic stress disorder.

How common is post traumatic stress disorder?

About 8% of US adults (including approximately 10% of all women and 4% of all men) will have post traumatic stress disorder at some point in their lives. The disorder is most common among adults who are single, divorced, or widowed, people who live in poverty, and young adults who are socially withdrawn. Women are more likely to experience post traumatic stress disorder after rape or sexual assault, whereas men are more likely to experience the disorder after combat. People who are regularly exposed to trauma (like veterans, abuse survivors, and first responders) experience post traumatic stress disorder at particularly high rates. For example, the recent wars in Afghanistan and Iraq caused post traumatic stress disorder in about 17% of returning veterans, and 30% of all veterans have the disorder. Natural disasters with lasting effects, like hurricane Katrina, the earthquakes in Japan and Haiti, and the Indian Ocean tsunami have caused PTSD in approximately 50-70% of survivors.

Is it possible to prevent post traumatic stress disorder?

The traumatic events that cause post traumatic stress disorder may not be foreseeable or avoidable and can happen to anyone at any time, so most scientists and mental health practitioners focus on early intervention instead of prevention. After a traumatic experience takes place, it is important to quickly identify people with the highest risk of developing post traumatic stress disorder and administer targeted programs that increase coping skills and decrease distress or fear. For example, soldiers use meditation, yoga, and acupressure to work through combat-related stress, while natural disaster survivors use crisis intervention counseling to process their feelings about what happened to them.

How is it treated?

Treatment for post traumatic stress disorder usually combines medication and therapy to support the patient in their time of need and improve their ability to cope with the world around them.
  • One effective psychotherapy for post traumatic stress disorder is cognitive behavioral therapy (CBT). CBT focuses on understanding and changing trauma-related thoughts, emotions, beliefs and behaviors. In doing so, CBT helps patients restructure their maladaptive thoughts and behaviors, and gives them a more effective way to manage future stress.
  • Other psychological treatments include hypnosis and exposure therapy to safely re-experience and process trauma, relaxation techniques to decrease overall feelings of stress, and group or family therapy to boost social support.
  • The medications used to treat PTSD are a type of antidepressant called selective serotonin reuptake inhibitors (SSRIs). SSRI’s block the reabsorption of serotonin, which improves communication and functioning throughout the brain. SSRI’s are particularly helpful in treating symptoms like anxiety and depression.

Consider the following

  • Post traumatic stress disorder is not a new disorder - military veterans have been reporting symptoms for hundreds of years! Throughout history, the disorder has had many different names - civil war veterans were often diagnosed with “soldier’s heart,” World War I veterans experienced “shell shock” and World War II caused “combat fatigue.”
  • Some people with post traumatic stress disorder benefit from having a service animal. Service dogs are trained to recognize symptoms and can help during crisis situations- they bring the person medication, wake them up during a nightmare, distract a person when they’re feeling anxious, and provide emotional support.

Want to join the conversation?

  • spunky sam blue style avatar for user Alexis Rd-m
    Hi, I saw on your second picture (the one with a brain's picture called "normal information processing and ptsd malfunctions in the brain") you wrote under "hippocampus" two parts, one of them has the title "OCD brain", is it a mistake or do we not distinguish in this case "OCD brain" from "PTSD brain"?
    (12 votes)
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  • starky seed style avatar for user Ari
    If someone were to be exposed to abuse but not undergo it (such as a child witnessing physical abuse between parents, witnessing substance abuse in the household, etc), could that person also develop PTSD? And would that fall under chronic trauma?
    (3 votes)
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    • aqualine ultimate style avatar for user Sterre
      Yes absolutely, in fact most countries' laws still classify situations like that as child abuse. Even if the child itself is not physically harmed, the emotional damage that growing up in unsafe households causes is just as much of a trauma and can still definitely cause things like PTSD
      (4 votes)
  • female robot grace style avatar for user tw486364
    Wrongful Convictions cause PTSD also.
    (4 votes)
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  • purple pi teal style avatar for user valvarez2015
    Is it more likely to affect on adults or children more?
    (4 votes)
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  • blobby green style avatar for user Maranda Markwood
    How does PTSD correlate with drug use?
    (3 votes)
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  • duskpin sapling style avatar for user Hannah Martin
    How can post-traumatic stress disorder affect the lives of a person? What can a person do to cope with ptsd? What can their family do to help with the person that has ptsd to get through their life without doing something irrational like committing suicide
    (2 votes)
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    • purple pi teal style avatar for user Sharon Wallace
      Someone with PTSD can become paralyzed to the point they can no longer function. They no longer care about personal hygiene. They don't go outside. They act out aggressively, or hide in constant fear. They can't hold a job, have friends, go to a movie, or do things people without PTSD take for granted. If you were living that kind of life you would not think it irrational to commit suicide. What family and friends can do is to recognize the symptoms of PTSD before it becomes that severe and get their friend/family member help. Treatment by a professional will help the person learn to cope with the events and the outcomes. The National Institute of Mental Health, SAMSA, and the Department of Veterans Affairs all have excellent resources for educating yourself on the signs of PTSD and links to local resources in your area. There is no prevention but there is treatment. Being there, getting them into treatment, and not belittling their feelings are the ultimate ways to help someone with PTSD. They are fighting both their mind and a conditioned physical response that has to be reprogrammed into a healthy and responsive mannner
      (2 votes)
  • duskpin ultimate style avatar for user Bob Bruer
    Re "the recent wars in Afghanistan and Iraq caused post traumatic stress disorder in about 17% of returning veterans, and 30% of all veterans have the disorder." These numbers are confusing... I would expect PTSD to increase risk of sudden death, so would expect prevalence among surviving veterans to be lower that 17% due to increased PTSD death. Or could I infer conflicts prior to Afghanistan and Iran produced a higher PTSD rate?
    (3 votes)
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  • duskpin sapling style avatar for user Hannah Martin
    Can a pet like a service dog help when a ptsd person needs some comfort?
    (2 votes)
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  • blobby green style avatar for user mhickey665
    I was wondering if the 'OCD' heading on the second picture was meant to say PTSD?
    (2 votes)
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  • piceratops tree style avatar for user noah86400
    Is OCD annoying to parents?
    (2 votes)
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