The Neurobiology and Impacts of PTSD

By Joanna Crifasi, STAR volunteer advocate

Post-Traumatic Stress Disorder (PTSD) is a psychological condition that can develop from witnessing or experiencing an emotionally disturbing or distressing situation. According to the National Center for PTSD, 8 million people in the U.S. live with PTSD each year (2017). PTSD can emerge from directly experiencing an event or indirectly experiencing the incident through one’s telling of their own experience or witnessing another person experiencing trauma. Professionals who experience immense distress from regularly dealing with instances of indirect, secondary trauma (e.g., law enforcement, counselors, medical personnel) sometimes experience a shift in themselves impacting their mood and causing symptoms of PTSD. This transformation is termed vicarious traumatization.

Experiencing distress after a traumatic event alone does not warrant a diagnosis. Over half of Americans experience a traumatic event within their lifetime, but only 7 to 8 percent of those individuals develop the disorder (Veterans Affairs, 2017). Types of PTSD symptoms experienced and their severity differ from person to person. The four main symptoms and signs of PTSD include invasive memories, avoidance, negative shifts in mood or thought, and changes in physical and emotional reactions (Mayo Clinic, 2019). Some specific symptoms include:

  • Significant changes in mood, arousal, reactivity, sleeping patterns or ability to focus
  • Changes in routine to avoid re-experiencing the event
  • Depression, anxiety, anger outbursts or impulsive behavior
  • Loss of memory or difficulty recalling events related to the trauma
  • Flashbacks, nightmares, or intrusive thoughts
  • Triggers, or cues such as words, events or people that were once neutral, now serve as reminders of the trauma and invoke negative emotions

A detailed list of the criterion used for official diagnosis can be found in the 5th edition of the “Diagnostic and Statistical Manual of Mental Disorders”, also known as the “DSM–5”.

Many situations contribute to the development of Post-traumatic disorder, some instances are:

  • Sexual assault
  • Physical or psychological abuse
  • Experiences in war
  • Witnessing death or losing a loved one
  • Bullying
  • Serious injury or illness
  • Spontaneous accidents (e.g., car wreck or house fire)

PTSD can be debilitating, causing problems in a person’s productivity, relationships, and mental health. In many cases, the longevity of psychological trauma exceeds the life of harmful effects on one’s physical well-being; cuts, scrapes, broken bones and bruises are certainly painful but eventually heal. On the contrary, psychological trauma can last anywhere from a month to a lifetime. This disorder is not a sign of weakness, but a biological condition that impacts men and women from all cultural, socioeconomic, ethnic and racial backgrounds. In serious cases of PTSD, the brain responds by undergoing observable changes, especially regions such as the prefrontal cortex, hippocampus, and amygdala—areas that play a primary role especially in regions of the brain responsible for cognition, memory, and response to stimuli. Below is a diagram, showing the brain regions along with their key function, that studies and research find to be most significantly impacted by post-traumatic stress disorder.

The amygdala, known as the “center for emotions” plays a key role in the regulation of emotions, memories and initiating survival instincts. When an organism is presented with a potentially harmful stimulus from the environment, the amygdala reacts by alerting the body’s fight, flight or freeze response. For instance, if a bee lands on a young boy’s shoulder, he has three options, he can either run, hoping to escape the insect, he can swat at the bee, or he can remain still until the bee flies away. The boy does not have time to evaluate all three options and their outcomes, thanks to his amygdala, he is able to act efficiently without much conscious thought. When a person experiences a stressful event, the amygdala releases a chemical called norepinephrine, which heightens activity levels resulting in an increased heart rate and an elevated state of arousal. Individuals with PTSD often experience more activity in their amygdala, resulting in more reactive startle response and more norepinephrine released into the body. Excess norepinephrine can give a person too much adrenaline, compromising one’s ability to reason logically and efficiently. Damage to ones’ amygdala inhibits ones’ ability to experience fear (Aggleton, 2000). Contrary to the hyperactive amygdala contributing to impulsive behavior, a hypoactive amygdala is problematic because the person is less likely to appropriately respond when in dangers.

Another brain region that is altered in victims with chronic PTSD is the “executive functioning center”, the prefrontal cortex (PFC), which works with the amygdala to regulate emotions and behavior. It plays an important role in accomplishing goals, abstract thinking, self-control and the initiation of behavior. Normal functioning brains have a PFC wired to counteract over-excitation in the amygdala, however, brains with PTSD often have a lower functioning PFC. Research shows patients with PTSD frequently experience a decrease in the volume of the ventromedial prefrontal cortex, a region that plays a role in regulating emotions and restraining impulsive behavior (Maynard, 2020). This exhibits why subjects with PTSD feel overwhelmed with stress and anxiety in instances where they are not actually in danger.

Along with the prefrontal cortex, the hippocampus plays a part in mediating stress and fear. This region also plays a primary role in cognition, learning, perception, and retrieval of memories. When a person undergoes trauma, they may be triggered by environments that resemble the place the instance occurred. This spatial association is largely due to the hippocampus, which helps us to differentiate the present from the past. When people feel stressed, the hypothalamus releases a hormone called cortisol, which helps regulate response to stress. However, as observed in animal studies, high levels of cortisol are thought to damage hippocampal cells. Brain scans show PTSD patients with chronic stress have hippocampal damage, reducing their size and function (Tull, 2019). Smaller hippocampi contribute to trauma survivors experiencing difficulty when attempting to recall past events and separate previous stressful experiences from current situations. The reduction in hippocampal volume helps to explain why a movie based on the beach, could invoke anxiety and fear in a shark attack victim.

Awareness of the neuroscience behind mental disorders, especially PTSD, is helpful to understand and support loved ones who live with them. Furthermore, professionals can provide more effective treatments when made aware of the brain areas that need additional stimulation or inhibition. There are many different approaches that can be taken to reduce PTSD symptoms. Six of the most frequent and productive treatments (Bhandari, 2017) are:

  • Cognitive processing therapy, one of the most common treatments for PTSD, is a treatment made up of therapy sessions that allow clients to talk with counselors or therapists about their trauma and feelings. This process encourages trauma victims to think about the event and work with a professional to develop healthy coping skills and aims to limit control PTSD has on the person’s daily routine.
  • Eye movement desensitization and reprocessing is a therapy where the client does not necessarily verbalize their feeling and experiences but internally processes them while focusing their attention towards a light, object or picture.
  • Prolonged exposure therapy, a more direct approach, has individuals face their trauma head-on working to relieve symptoms by confronting them. For instance, a therapist might have their client write or verbally report significant events that are causing stress, then repeat or reread the events and tell about the symptoms they experience because of the instance(s).
  • Drug therapy, also known as pharmacotherapy, which can help balance chemicals in the brain and is usually most beneficial when used with a form of behavioral therapy. Doctors usually prescribe medications that inhibit or encourage the release of chemicals like norepinephrine or serotonin. Other medications may be prescribed to help mental illnesses and symptoms that commonly occur with PTSD, like anti-depressants, benzodiazepines or anti-psychotics.
  • Stress inoculation training, a form of cognitive-behavioral training that requires no discussion of the events that contributed to the PTSD, but focusing on coping with the symptoms by learning various breathing and massage techniques

Listed below are four recommendations for individuals working to overcome PTSD (Smith, Robinson, Segal, & Segal, 2019).

  • Challenge your sense of helplessness. Surround yourself with healthy activities and push yourself to overcome the challenges. Remind yourself that healing is a process and use adversity as motivation to persevere.
  • Stay active. Exercising and spending time outdoors proves to increase the release of endorphins and improve your mood.
  • Surround yourself with support. Reach out to a trusted friend or family member, seek out a mental health professional, or get involved in the community by participating in volunteer opportunities, join a support group or an organization involved in an area of interest.
  • Establish and maintain healthy habits. Remember to take time to relax, do things you enjoy and aim to get 7 to 9 hours of sleep every night. Also, focus on having a healthy diet and avoid substances that could interfere with positive treatment.

Professionals are reluctant to say PTSD can be cured, because once exposed to trauma there is always a chance that previously experienced symptoms could return (“Is PTSD Curable?”, 2020). Although, PTSD can be managed, and the influence of symptoms can be minimized with treatment. It is crucial for people suffering from PTSD to know recovery is possible and PTSD does not have to control your life.



Works Cited

Aggleton, J. P. (2011). The amygdala: a functional analysis. New York: Oxford University Press.

Bhandari, S. (2017). 6 Common Treatments for PTSD (Post-Traumatic Stress Disorder). Retrieved from

Is PTSD Curable? (2020). Retrieved from

Maynard, E. (2020). Correlation Between Structures of the Brain Function and PTSD. Retrieved from

Mayo Clinic. (2018). Post-traumatic stress disorder (PTSD) Retrieved from

Smith, M., Robinson, L., Segal, R., & Segal, J. (2019). Post-Traumatic Stress Disorder (PTSD). Retrieved from

Tull, M. (2019). How Damage to the Brain’s Hippocampus May Play a Role With PTSD. Retrieved from Veterans Affairs. (2018, September 13). How Common is PTSD in Adults? (Retrieved from


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