How Psychological Trauma Affects The Brain

It is widely recognized that trauma can contribute to emotional problems and psychological disorders. Having been the victim of abuse, neglect, or violence can increase the likelihood of developing depression, anxiety, and problems maintaining healthy boundaries and healthy relationships.

Neuroscience research, however, has demonstrated the manner in which trauma can actually contribute to changes in the structure and function of your brain.

These changes occur in three key areas of the brain: the amygdala, which is your emotional and instinctual center; the hippocampus, which controls memory; and the medial prefrontal cortex, which is responsible for regulating emotions and impulses. All three parts work together to manage stress.?

What is Trauma?

Psychological trauma occurs as the result of an extraordinarily stressful event that diminishes or destroys your sense of security and involves a threat to life or safety. Traumatic experiences exceed your ability to cope, and your ability to integrate emotions involved with the experience. Psychological trauma can cause you to feel helpless and leave you struggling with upsetting emotions, memories, and anxiety. It can also leave you feeling numb, disconnected, and unable to trust others. It can change the way you interact with and relate to individuals around you.

Any situation that leaves you feeling overwhelmed and frightened can be traumatic, even if it doesn’t involve physical harm. It’s not the objective facts that determine whether an event is traumatic, but rather your subjective emotional experience of the event. A situation may be determined to be highly traumatic by one person, and only moderately disturbing to another. The more frightened and helpless you feel, the more likely you are to be traumatized.

Being the victim of physical violence, rape, or assault can lead to the development of trauma symptoms, as can experiencing war, natural disasters, or life-threatening accidents. Psychologists have recently learned that being subjected to emotional abuse and neglect in childhood can be just as psychologically damaging as being the victim of physical or sexual abuse. Similarly, being involved in an adult relationship with an abusive or narcissistic partner can also lead to the development of anxious distress, hypervigilance, and feelings of helplessness that are associated with trauma.

Traumatic stressors such as these can lead to the development of posttraumatic stress disorder (PTSD) which affects about 8% of Americans at some point in their lives. PTSD is characterized by specific symptoms including flashbacks, intrusive thoughts, nightmares, avoidance issues, sleep disturbances, changes in memory and concentration, and startle responses.?For some trauma victims, PTSD may become a lifelong problem if they don’t receive proper treatment.?Trauma can also contribute to depression, anxiety, substance abuse, dissociation, personality disorders, and health problems.

Trauma can result in acute and chronic changes in neurochemical systems and specific brain regions, which may contribute to long-term changes in brain circuits involved in the stress response.

Trauma Can Impact Key Regions of the Brain:

Psychological trauma has the potential to significantly impact the structure and function of three key brain areas: the Amygdala, the Hippocampus, and the Medial Prefrontal Cortex (mPFC). Here is a look at how these changes take place:

The Amygdala Becomes Overactivated and Increases in Size

Jennifer was 17 years-old when she left her small hometown to attend her freshman year of college at a major university. Her new roommates encouraged her to get out, explore the campus and accompany them to and a party. Sometime around midnight, Jennifer realized she had had too much to drink and lost track of her friends. A boy she met at the party offered to walk her back to her dorm and Jennifer accepted.

Halfway back to her dorm room, the boy began aggressively kissing her, touching her inappropriately, and taking off her sweater. Before Jennifer knew what happened, the boy was on top of her, removing her clothes. Completely taken off guard, Jennifer fought and tried to flee, but her attacker overpowered her.

After the assault was over, Jennifer stumbled back to her dorm room and began to cry. The next several months were a blur. She was constantly on high alert and loud noises made her jump. She refused to walk around campus after dark, and she avoided social situations and gatherings. She frequently felt short of breath and her heart raced if there was a lot of activity near her. Shortly after, she had her first panic attack. Gatherings with friends that she used to enjoy now made her nervous, edgy, and irritable. When meeting new classmates and friends, she was constantly assessing whether or not they were safe and to be trusted.?

The amygdala is an almond shaped set of neurons located deep inside the brain which is responsible for the generation of emotions. It is commonly referred to as the "fear center" of the brain.

The amygdala is designed to detect and react to people, places, and things in your environment that could be dangerous. This is important for safety and survival. The amygdala is sensitive to potential threats to your safety, and is involved in the processing, interpreting, and integration of emotional functioning.

The amygdala is where fear learned from past experience is stored. The amygdala receives input directly from sensory systems throughout the brain. It then processes and determines the emotional value of simple sensory input, complex multisensory perceptions, and complex cognitive abstractions.

When you experience a traumatic event, your amygdala becomes activated. It does this by releasing stress hormones such as cortisol into your body. This triggers a fight-or-flight response which results in physical changes in your body. Your heart rate may go up. Your breathing may become shallow and rapid. You may begin to sweat or shake. This is your body's way of preparing you to take action to protect yourself. This is a survival mechanism, and evolution programmed you in this manner to insure you would be prepared to run or fight when faced with a life-threatening situation. During her traumatic assault, Jennifer’s amygdala became activated, releasing increased levels of the hormone cortisol which triggers a fight or flight response in the body.

An individual's amygdala senses danger and can be triggered by environmental conditions, such as a loud noise or seeing someone that appears threatening. When the amygdala is triggered, it sends signals to other parts of the brain, including the hippocampus and prefrontal cortex. This causes you to experience fear, anxiety and other negative emotions.

When an individual experiences trauma, their amygdala may go into overdrive. When this happens, the person becomes hypervigilant and is constantly on the lookout for anything that may be a sign of danger. This can lead to an amygdala hijack, which occurs when your amygdala takes over in response to stimuli and triggers a powerful fear response before rational thought can occur. Consequently, individuals with trauma tend to react more quickly out of fear rather than out of logic or reason. Your reactions may be disproportionate to the situation, simply because your amygdala is already activated and in overdrive, working to protect you. After Jennifer's assault, neutral situations in her busy college environment were suddenly interpreted as possibly dangerous, including situations that used to be enjoyable for her, such as large gatherings with friends. The high cortisol levels and consistent activation of the amygdala caused Jennifer's brain to become "wired" for survival in a hostile environment and this significantly weakened her capacity for trust.

The amygdala orchestrates the response to this emotional information by sending projections to brain areas involved in motor movement, as well as the autonomic nervous system, and the neuroendocrine areas of the Central Nervous System (CNS). Fearful situations stimulate the brain to activate the sympathetic nervous system and adrenal glands, causing the release of stress neurotransmitters and hormones. These chemicals activate the "flight or fight" response which includes an increase in heart rate to facilitate the delivery of blood to working muscles. You may become more alert and focused on the threat, experience increased vigilance, and a decrease in peripheral awareness. This entire sympathetic nervous system response is designed to prepare the individual for action.

It is important to note that even though the amygdala reacts to perceived danger, it does not mean that you are actually in danger. It just means your brain is reacting as if you were.

After trauma, the amygdala can become even more sensitive to potential threats, leading you to closely monitor your surroundings to ensure you are safe and causing you to have strong emotional reactions to people, places, or things that might be threatening or that remind you of the trauma.

This heightened attention to potential threats can impact the behavior of both children and adults. For children, this heightened focus and reactivity to potential threats can make it difficult to pay attention in school, go new places, or interact with people they don’t know.

In adults, this process can contribute to problems in relationships. The traumatized individual begins to act like a Transportation Security Administration (TSA) agent at the airport: everyone around them is believed to be a terrorist until proven otherwise. Everyone they meet including new colleagues, potential romantic partners, and social acquaintances, have to go through a mental screening process before they can be considered safe and trusted. This can impair the person's ability to form close relationships, to advance at work, and to feel comfortable in social settings.

If the individual does not seek therapy or resolve the traumatic triggering, the amygdala will likely continue to remain sensitive to potential threats. As a result of this process, over time the amygdala can actually increase in size due to increased neural pathways and synaptic growth. This allows it to become even more sensitive to threats, making it easier for fear memories to be triggered. Over time, this can lead to chronic anxiety and fear-based behaviors such as avoidance and hypervigilance.?For survivors of sexual assault and other traumas, the amygdala can remain activated long after the threat has subsided. In this manner, trauma has produced a re-calibration of the brain's alarm system, and an increase in stress hormone activity. As long as the trauma is unresolved, these changes in the brain can last a lifetime.?

Fortunately, due to neuroplasticity of the brain (the brain's remarkable ability to rewire and heal itself), the amygdala can heal from trauma and the increase in size can be reversed. It is possible for those who have experienced trauma to find relief through EMDR therapy or other forms of treatment. With practice, it is possible to reduce fear-based thoughts, regulate emotions more effectively, and even become more resilient to future trauma.

The Hippocampus Shrinks

Adam was eight years-old when his mother became remarried to a man named Tom. Tom was an abusive alcoholic who rarely missed an opportunity to tell Adam how worthless he felt he was. Tom had a habit of coming home from the bar late at night and physically abusing Adam's mother. By the time Adam was nine, Tom progressed to beating Adam and his sister as well. Adam struggled to hide the bruises on his arms and legs from his teachers and peers. One night, Tom came home drunk and Adam's mother attempted to defend herself. Adam peeked down the dark hallway from his bedroom to witness Tom stabbing his mother and his mother screaming. While his mother was in the hospital recovering, Adam and his sister were sent to live with a foster family.

Over the next several months, Adam struggled in school. He had difficulty learning new information, although he previously had been one of the top students in his class. When he did learn information, he had trouble applying it. He struggled to remember math facts and to turn in assignments on time, even when he had completed them. He began to have emotional outbursts that were uncharacteristic of him.

When Adam was in his thirties, he entered therapy to address difficulties with emotional dysregulation. During his first session, he began by telling his therapist, "I really don't remember much of my childhood."

The hippocampus is a brain structure located in the temporal lobe that is important for memory formation and recall. It helps to encode new memories, store them, and retrieve them when needed.

The hippocampus also plays an important part in the recall of emotional memories. Have you ever noticed how a particular scent might trigger a strong memory? It’s the hippocampus that plays a role in this connection.

After experiencing trauma, individuals may have difficulty forming new memories or retrieving old ones because of changes in the hippocampus. These changes can also lead to difficulty controlling emotions, increased stress hormone activity, and a heightened fear response.

The hippocampus is also critical to the process of learning. Children and adults who have experienced trauma have been found to have increased difficulty in the ability to learn and remember information about the environment. As a result, they are unable to adequately process information regarding how to tell if one situation is safe and another is dangerous, leading them to experience harmless situations as scary. For example, a person who has experienced trauma may have difficulty distinguishing between activities that are dangerous (e.g., walking down a dark alley) and safe (e.g., walking around a dark corner at home).

The hippocampus also plays a key role in various activities of the autonomic nervous and neuroendocrine systems. Stress hormones and stress-related neurotransmitter systems have the hippocampus as a target. Various hormones (e.g., cortisol) appear to alter hippocampus synapse formation, thereby causing actual changes in gross structure and size. Repeated stress inhibits the development of neurons and atrophy of the hippocampus can occur. These neurobiological changes are related to some of the problems with memory and learning found in stress-related neuropsychiatric syndromes, including posttraumatic stress disorder (PTSD).

The hippocampus also plays a vital role in flexible and goal-directed behavior. Intact hippocampal activity is required for forming and reconstructing relational memory (required for remembering arbitrary associations between objects or events) associated with flexible cognition and social behavior. Many studies have revealed that trauma-related changes to hippocampus can impair flexible use of information and produce maladaptive behavior.

Research has found that following traumatic experiences, the hippocampus can actually shrink in size. This is because of increased levels of cortisol, a stress hormone released by the brain during traumatic experiences. High levels of cortisol can lead to reduced hippocampal volume and decreased hippocampus activity, which can result in difficulty forming new memories or remembering old ones. This is true of individuals suffering from PTSD, as well as people subjected to chronic, ongoing stress. The hippocampus also shrinks following traumatic experiences because the hippocampal neurons are not as able to form new connections, and this hampers memory formation.

When the hippocampus shrinks in size, the individual can develop learning difficulties, memory impairment, and emotional disturbances, as well as problems with impulse control and self-regulation. These changes in the hippocampus likely contributed to the difficulties Adam demonstrated with learning, memory, and emotions. The outcome is decreased activity in the hippocampus, as well as changes in the connection between the hippocampus and the amygdala.

The hippocampus plays an important role in regulating the amygdala. Specifically, it helps to inhibit the amygdala's responses so you can think more rationally and respond in appropriate ways instead of reacting out of fear or panic. With hippocampus shrinkage due to trauma, this part of the brain is less able to control the amygdala’s reactions and you may be more prone to feeling overwhelmed by fear and anxiety.

Studies also suggest that traumatic memories affect how we interpret current events and take action, even when we are not consciously aware of the trauma-based thoughts dictating our behavior. Long-term exposure to traumatic events can lead to changes in the brain's neural pathways and structures, which can cause difficulties with memory, attention, concentration, and information processing. This can have a serious impact on day-to-day functioning and quality of life.

Although the hippocampus can shrink in size after trauma, it is still possible to restore hippocampal functioning. Research suggests that psychotherapy and other therapeutic interventions such as EMDR can help individuals process traumatic experiences, heal emotionally, and regain their ability to process and store memories.

The Medial Prefrontal Cortex Shuts Down

Sarah was the 35 years-old mother of twin toddlers and was spending a weekend at home with her children while her husband was away on a business trip. Shortly after she put the children to bed, she put on her pajamas and her favorite robe, and reclined on the couch to watch old movies. Exhausted from a long day with the twins, she quickly felt herself drifting off to sleep.

A few hours later, she was awakened by the smell of smoke and the piercing blare of her smoke alarm. As she ran toward the twins' bedroom, she passed the kitchen and was horrified to see the entire room engulfed in enormous flames that reached the ceiling and covered the walls. The roar of the flames sounded like a freight train. Thick smoke filled the back of her throat and made her eyes burn.

Frantically, she pulled the children from their beds, felt her way to the door, and dragged them outside to safety. She ran back in the house for their beloved beagle, but couldn't find him. The smoke and flames prevented her from going past the living room and sadly, she knew her dog was trapped on the other side of the flames. Sarah ran back outside to her crying twins and was grateful to discover her cell phone was still in the pocket of her robe! Her hands were shaking as she dialed 911. She stammered to describe her situation to the operator. The house now engulfed in flames and their dog still inside. Sarah stuttered and could not find her words. She just stared at the inferno before her and couldn't articulate what happened to the rescuer on the other end of the phone. When the operator asked Sarah what her address was she replied, "I don't know! Just get here now!" When the firefighters arrived and began to put out the flames, Sarah was observed to be sitting on the ground, tightly hugging her knees and staring blankly into the distance. When authorities attempted to ask her about the fire or if others were in the house, she was nonresponsive.

Over the next several weeks, Sarah struggled with difficulties of attention, concentration, and focus. She had trouble planning meals for the children, and always seemed to be forgetting something. While leaving the grocery store, she accidentally backed her car right into another vehicle. Sarah told her neighbor that she felt "scattered" since the fire and struggled to remember what she was doing.

The medial prefrontal cortex (mPFC) is found in the anterior portion of the brain, behind the forehead, and is known as the rational, thinking part of the brain. The mPFC is the region of the brain known for managing executive functions, which are abilities such as planning, organization, decision making, and problem solving. The mPFC also builds reciprocal connections with brain regions that are implicated in emotional processing (amygdala), memory (hippocampus) and higher-order sensory regions (within the temporal cortex).

Recent advances suggest the mPFC plays an important regulatory role in numerous cognitive functions, including?attention, inhibitory control, habit formation, working memory, spatial reasoning, and long-term memory.

After an individual experiences a significant trauma, it is not uncommon for the medial prefrontal cortex to "go offline" or shut down. When this happens, the person may experience problems with attention, concentration, confusion, and memory. After escaping from her burning home, the trauma of the event caused Sarah's prefrontal cortex to go offline, making her appear to be in a daze, and making it difficult for her to tell authorities what happened or describe the chain of events. If trauma symptoms persist, this decreased activity in the mPFC can lead to reduced volume in this area of the brain.

Decreased activity in the mPFC makes it difficult for you to think in a clear and purposeful manner and to concentrate. This can last a few hours, or it can last weeks or months, depending on the severity of the trauma, your perception of the event, your emotional reaction to it, your prior level of resilience, and even your previous psychological functioning.

Following situations such as Sarah's house fire, some people may struggle to make decisions and have difficulty recognizing dangerous situations or potential harm to themselves. This can also lead to impulsive behavior, not being able to focus on tasks, and poor judgement. In addition, when the mPFC is inhibited due to trauma, it can interfere with a person’s ability to regulate their emotions. This can cause them to experience anxiety, depression, and difficulty controlling their impulses.

The mPFC helps to control the activity of the amygdala and is involved in learning that previous threats are no longer present. This can help reduce the amygdala’s over-activation and allow the individual to better regulate their emotions. In people who have experienced trauma, the mPFC can be weakened, making it more difficult to control amygdala activity and cope with traumatic memories.

Connections between the mPFC and amygdala are sometimes not as strong in children who have experienced trauma. As a result, the mPFC is not as effective at reducing reactivity to people, places, and things that are no longer a threat of danger. This can lead to persistent elevations in fear and anxiety regarding reminders of the trauma they experienced.

It is only through therapeutic interventions that these changes in the brain can be reversed.?By working with a skilled therapist, individuals can develop new neural pathways and strengthen plasticity in the mPFC, the hippocampus, and the amygdala. Trauma-informed therapies such as EMDR help people learn to manage the effects of their traumatic experiences and regain control over their thoughts and emotions.?

Trauma Affects Your Brain Processing in Three Important Ways

As a result of these changes in the amygdala, hippocampus, and mPFC, trauma can contribute to changes in your ability to regulate fear, recall memories, and manage emotions.

Regulating Fear

When you experience trauma, especially chronic trauma that is sustained over a period of time, your survival instincts may become out of whack. You may not be able to differentiate between a threat and something totally safe, and you may experience fear more often than you used to. The increased activity in your amygdala can leave you feeling on edge or in danger. The continual presence of fear may remind you of your trauma, which leads you to feel even worse. You might experience chronic stress, hypervigilance, and anxiety because your brain is confused about how to respond. After a traumatic event, your brain can remain on high alert for danger. This constant state of being on edge can be exhausting. This state of hyperarousal can also lead your body to produce extra stress hormones, like norepinephrine and adrenaline. These hormones keep your body in a state of fight or flight, which can be helpful in a true emergency, but not when you are actually in a safe setting. This difficulty in regulating fear can keep you on edge and prevent you from enjoying your normal activities of daily living.

Recalling Memories

Following trauma, you may have increased difficulty recalling memories. This is known as memory fragmentation. Memory fragmentation occurs when memories are stored in a fragmented way, with certain details being more easily recalled than others. This can make it difficult to recall specific details or the order of events. People may be able to remember the general feeling of an event but struggle to remember the specific details that occurred. You may recall bits and pieces of the trauma such as isolated images, sounds or smells, but not remember the full sequence of events or how it ended. Due to changes in the structure and function of the hippocampus following trauma, you may have difficulty converting short-term memory to long-term memory, and difficulty remembering simple things throughout your daily life. These changes can make it harder to recall memories, or they can bring traumatic memories to the forefront of your mind. The hippocampus also helps us differentiate between past and present memories, so when it’s hyperactive it can dredge up painful memories of your trauma. When your mind is constantly replaying traumatic memories, it can be scary, exhausting, and triggering.??

Managing Emotions

Your ability to manage your emotions can be impaired after experiencing trauma. This can cause you to become overwhelmed with intense emotion, such as sadness, anger, guilt and shame. The memory of the traumatic event may trigger similar emotions in other situations as well. In some cases, people struggle to feel any emotion at all, or they are unable to adequately describe their emotions. These are known as “alexithymic” responses. It is common for people to experience emotional numbness following trauma, which can be disorienting and make it difficult to manage daily tasks or relationships. When you are overwhelmed by strong emotions or unable to feel any emotion at all, it can affect your ability to cope with stressful situations, and to manage daily living.

We've discussed the manner in which trauma can contribute to changes in the medial prefrontal cortex (mPFC). The mPFC of your brain deals with emotional regulation, attention and decision making. Instead of becoming hyperactive, like the amygdala sending out stress hormones, the mPFC becomes hypoactive, or less active. Instead of regulating your emotions and using reason to make decisions like it normally would, your prefrontal cortex doesn’t intervene. Normally, if your amygdala is hyperactive and sending out stress signals, your prefrontal cortex can decide if the threat is valid, and calm you down if it’s not; however, trauma creates a situation in which the prefrontal cortex doesn’t do its job to calm you or regulate your emotions, so you’re left on a rollercoaster.

The prefrontal cortex’s lack of regulation can also leave you vulnerable to reactive anger and impulse control issues, which can make social situations and relationships more difficult. Your brain is an incredibly complex structure, so when there is damage to it, whether physically or through trauma, it can have serious effects.?

EMDR Therapy Can Help

Eye Movement Desensitization and Reprocessing (EMDR) Therapy can reduce the effects of trauma on the brain and release trauma stored in the body. EMDR is a specialized type of therapy used to assist in trauma recovery. This technique helps with managing symptoms associated with PTSD, anxiety, depression, and other psychological issues related to traumatic experiences. EMDR uses bilateral side-to-side eye movements, tapping, or other forms of bilateral stimulation to help modify the way the brain processes information.

EMDR therapy is designed to resolve unprocessed traumatic memories in the brain. It changes the way memories are stored in the brain. The EMDR therapist does this by leading you through a series of bilateral side-to-side eye movements as you recall traumatic or triggering experiences in small segments, until those memories no longer cause you distress.

Stress responses are part of our natural fight, flight, or freeze instincts. When distress from a disturbing event remains, the upsetting images, thoughts, and emotions can create an overwhelming feeling of being back in that moment or frozen in time.

EMDR therapy helps the brain process these memories and allows normal healing to resume. The experience is still remembered, but the fight, flight or freeze response from the original event is resolved.

As a trauma therapist, I have successfully used EMDR for several years to help patients recover from trauma associated with many diverse experiences including abuse, neglect, assaults, accidents and natural disasters, as well as trauma sustained from narcissistic abuse. I've discovered EMDR to be the most effective form of treatment for healing unprocessed memories, resolving traumas, and restoring functioning.

Whether you suffered a single traumatic event, or have a long history of multiple traumas from abuse, neglect or abandonment from childhood, EMDR therapy can help your brain process and resolve those painful memories.

Healing from psychological trauma is essential for living in peace. With appropriate therapy, you can move toward trauma resolution, gain insight into your inner world and your past experiences, reverse the structural and functional changes that may have occurred in your brain, and discover a newfound sense of happiness and freedom. To begin your healing journey today, make sure to seek out a qualified EMDR therapist. You deserve to live a life of joy and peace.

Dr. Susan Spicer is a licensed psychologist, neuropsychological expert, certified brain health coach, and trauma therapist. She specializes in helping individuals heal from trauma and narcissistic abuse. For free resources from Dr. Spicer, click here.