Although she didn’t witness the event herself, Heidi Horsley , PsyD, found herself replaying the last moments of her brother’s life again and again in her mind. He died in a car accident after hydroplaning during a rainstorm.

“That narrative kept going over and over, and I couldn’t get the loop out of my head,” she says. With each replay, she recalls, she ruminated on whether her brother suffered before his death — and she became increasingly worried someone else was going to die. “The safe predictable world you once knew is gone. When my brother died, I didn’t feel like my parents could protect us. I felt my brother died, so I could die.”

Dr. Horsley’s younger brother died when she was 20 years old. Her experience as a young adult eventually prompted Horsley to become a therapist who specializes in grief and trauma. Now an adjunct professor at Columbia University in New York City and the executive director of the Open to Hope Foundation, Horsley says trauma, and its impact on mental health, is widely misunderstood.

Society often expects survivors of emotional trauma to recover much faster than is realistic — to stop talking about the event and move on in a matter of weeks or months. As a result, many individuals come to believe they are suffering from a mental health condition like post-traumatic stress disorder (PTSD) when their reaction may be not only normal but healthy, she explains.

“That’s where people get it wrong,” Horsley says. “[If, for example,] you were assaulted, it is normal to feel like the weight of the world is on you and you have no energy.”

While a certain percentage of individuals do develop mental health conditions, especially PTSD and depression, after a traumatic event, most people recover naturally with time and good social support. In fact, a strong emotional response to trauma may be key to ensuring long-term recovery, Horsley says.

Common Questions & Answers

What is trauma?

Psychologists define trauma as an emotional response to a terrible event. Symptoms can be emotional or physical and include: shock, denial, flashbacks, headaches, and nausea. Physical trauma is something different, involving a serious injury to the body.

What does trauma feel like?

People who experience trauma tend to have intrusive thoughts about the trauma and have a hard time not thinking about the experience. Shock and denial are common responses in early trauma stages, which could then progress to unpredictable emotions and flashbacks.

What are the main types of trauma?

Trauma can be acute, chronic, complex, or intergenerational. These types of trauma may show up in people in many different ways. One way is PTSD, a diagnosable condition you can develop as a result of trauma. Other ways may include depression, anxiety, and difficulty coping with emotions.

How do I cope with trauma?

Social support is often important when it comes to processing and working through trauma. Family, friends, and other trusted individuals can help you feel seen and validate your emotions. Making time for self-care is also important.

What are the long-term consequences of trauma?

Trauma affects everyone differently. Some long-term consequences can include trouble with attention and short-term memory, decreased sense of pain or fear, and trouble processing sensory inputs. Other effects can include chronic sleep, cardiovascular, neurological, and musculoskeletal problems.

What Is Trauma, and What Causes It?

In both popular culture and the medical field, the term “trauma” can cover a vast array of experiences.

In psychology, trauma is an emotional response to a terrible event like an accident, rape, or natural disaster. Shock and denial are typical short-term responses, and unpredictable emotions, flashbacks, strained relationships, and even physical symptoms like headaches or nausea are common longer-term symptoms.

Physical trauma is something different, involving a serious injury to the body, such as a deep cut or broken bones.

Psychological trauma generally stems from an experience that causes a person to believe in that moment that they, or someone else, is about to die, according to April Naturale, PhD , the assistant vice president of national crisis and wellness programs at Vibrant Emotional Health in New York City, who specializes in helping individuals and families cope with traumatic stress.

These kinds of events activate our fight-or-flight instinct, a stress response that triggers hormones to increase heart rate and prepare the body for action. This process also dials down activity in the parts of our brain that help us think critically and analytically (an energy-preserving mechanism to help us act more quickly in a moment of crisis).

In some cases, Dr. Naturale says, the brain stays stuck in this threat mode for months or years after an incident, which may lead to problems with concentration, sleep, relaxation, and general enjoyment of life.

“As best we know from studies of brain scans, trauma leads people to shift from being focused on paying attention to day-to-day life in an ordinary way, where they’re learning and exploring, to survival mode,” says Julian Fo rd, PhD, a professor of psychiatry at the University of Connecticut School of Medicine in Farmington. “All you’re thinking about is how to get through the experience and protect yourself and others.” (A review article outlines some of the brain regions known to be affected by trauma.)

Genetics and an individual’s natural risk of mental illness appear to play a role in who will develop lasting symptoms after a traumatic experience — but so does the kind of event that caused the trauma.

Life-threatening events that are not caused by humans, such as natural disasters, disease, and even traffic accidents can cause lasting mental health issues, but the percentage of people who develop PTSD following these traumas is typically less than after physical or sexual assault, Naturale says.

Intentional violence is different. Terrorism, shootings, rape, and other human-caused threats roughly double the odds that the victim will experience mental health effects, according to Naturale.

It seems easier for people to comprehend events involving human error or that things like natural disasters are out of our control, Naturale says. Intentional violence tends to be tougher to accept, she explains.

“What we don’t understand is when someone decides to randomly hurt, kill, or maim a group of people,” Naturale says. “We don’t like to think that anyone might kill us for no reason.” The randomness of certain traumas (whether they’re intentionally inflicted or not) can also be difficult to grapple with.

The number and duration of traumatic events a person experiences also significantly increases his or her mental health risk. Most people can cope with and recover from a single trauma. But when they experience multiple similar events, or when a single crisis persists for an extended period of time, the brain doesn’t have adequate opportunity to heal, Naturale says.

This may be why PTSD and other major mental illnesses are significantly more prevalent in combat veterans (as is supported by much research), she says — the continuous threat of death causes their brain to remain “flooded with stress hormones that cause physical, cognitive, and emotional problems.”

What’s the Difference Between Trauma and PTSD?

While it is normal to experience emotional distress in the immediate aftermath of a traumatic event, PTSD is considered a disorder — a mental state that prevents normal day-to-day functioning. In PTSD, symptoms associated with acute stress do not lessen over time, indicating the brain has been unable to heal and has become stuck, as Naturale says, in the fight-or-flight state. PTSD is only diagnosed if symptoms are still present after more than a month has passed since the traumatic event.

PTSD involves a set of four symptoms: intrusive memories of the traumatic event (often taking the shape of nightmares or flashbacks); hypervigilance for signs the traumatic event may happen again; avoidance of people, places, or things associated with the trauma; and negative changes in mood, self-esteem, or beliefs about the world.

Experiencing trauma after a distressing event may lead to one or two of these symptoms, Naturale says. For example, some people who have experienced intimate violence may have dissociation or avoidance, she says. “Having all four of them, plus an inability to function, is likely PTSD.”

PTSD, however, is not the only mental health condition associated with trauma, says Arianna Galligher, the associate director of the stress, trauma, and resilience trauma recovery center at the Ohio State University Wexner Medical Center in Columbus. Trauma may exacerbate mental health conditions that existed before the event, or people may develop symptoms of conditions such as depression or anxiety disorders for the first time in the aftermath of traumatic experiences.

“A lot of people who have experienced traumatic situations may develop a major depressive disorder or anxiety symptoms, rather than PTSD,” Galligher says. “What we really look for in terms of diagnosis is, what’s going on with you, and how do your symptoms impact day-to-day functioning?”

People who fall into a depressed state after a trauma, Horsley says, may feel as though “the world we once knew is over.” They may experience feelings of worthlessness or helplessness, believing there is nothing they can do to prevent future traumatic events, and that life is no longer worth living.

Other people may become so determined to prevent the trauma from happening again that they develop anxiety disorders. They may become extraordinarily cautious and even may develop rituals that they feel will keep them safe, to the point where they may even appear to have obsessive-compulsive disorder (OCD), according to Dr. Ford.

Survivors of trauma may develop these disorders independent of PTSD, or PTSD may co-occur with other mental disorders. Major depressive disorder was the second-most common mental health condition reported after 2008’s Hurricane Ike, after PTSD.

Depression is also the most common disorder to co-occur with PTSD. The majority of people who develop PTSD will be diagnosed with more than one mental health condition.

Regardless of which direction the symptoms go, the root of the problem is typically control, Ford says. “The essence of trauma is it takes control away from you or someone you care about,” he says. How a person deals with that loss of control — giving up or redoubling their vigilance — may determine which set of symptoms they experience.

Other Types of Trauma

For emotional trauma that is not PTSD, psychologists have come up with several categories.

Prolonged Trauma

When a person is exposed to a prolonged human-caused trauma from which they cannot escape — as in situations such as child abuse, domestic violence, or discrimination — the brain often suppresses emotional reactions in order to remain in survival mode for an extended period of time, Ford says. Later in life when the threat is removed, these emotions begin to emerge, often in unexpected or overwhelming ways.

This can lead people to experience panic attacks or fits of rage. In other cases, Ford says, people exposed to prolonged trauma develop dissociative episodes where they feel disconnected from their own lives. They may experience a sense that things happening to them are not real, or repeatedly zone out and lose track of time.

Waves of seemingly inexplicable emotions may drive some people to self-medicate and develop addictions; others may face social rejection in response to their outbursts, essentially adding new traumas to the old one, Ford says.

Complex Trauma

Ford and some other psychologists advocate for the creation of a new diagnosis, termed complex post-traumatic stress disorder (or CPTSD), which may arise as a result of this cycle of emotional retraumatization after prolonged traumatic episodes.

In addition to the symptoms associated with PTSD, the proposed criteria for CPTSD would include symptoms such as impulsive, aggressive, or self-destructive behavior; unstable personal relationships; persistent dissociation and an unstable sense of self; and difficulty with emotional regulation. Those with CPTSD may also complain of physical symptoms that cannot be tied to a physical cause.

Developmental Trauma

Ford supports the creation of another diagnosis, developmental trauma disorder, for those exposed to repeated or prolonged trauma during early childhood. Proponents of this new diagnosis argue that while less than a quarter of children exposed to early trauma will show signs of PTSD, the majority will develop symptoms such as inattention, poor impulse control, aggression, risk taking, and difficulty regulating emotions. These children often receive a mishmash of diagnoses such as anxiety, ADHD, oppositional defiant disorder, depression, and conduct and attachment disorders.

It should be noted, however, that neither condition (complex PTSD or developmental trauma disorder) is currently in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5, a classification of mental disorders published by the APA and used by mental health professionals in the United States), and not all psychologists agree they should be added. Those who oppose the addition of the new diagnoses argue the conditions they attempt to describe are already encapsulated by other disorders already included in the diagnostic manual. Others have argued that stress and trauma-related disorders such as PTSD, CPTSD, dissociative disorders, and some personality disorders should be collapsed into a single PTSD-spectrum disorder, as has been done with autism.

Intergenerational Trauma

Traumatic experiences may also have downstream effects when they contribute to intergenerational trauma, defined as a process by which the descendants of a traumatized individual or population may be exposed indirectly to the traumatic experience.

The exact means of exposure to intergenerational trauma is not yet fully understood, and may vary from one situation to the next, according to Galligher.

Its effects may be felt across cultures of people who have been displaced, enslaved, or subjected to genocide, according to Ford. Stories of these events may be passed down through the generations, transmitting the long-term effects of systemic disadvantages that result from the loss of homes and homelands, poverty, and discrimination.

Intergenerational trauma may also occur as a result of mental health symptoms, abuse, or exposure to violence that influence parenting skills.

Individuals may become emotionally volatile or withdrawn as a result of experiencing trauma, and these symptoms may create new adverse experiences for their children, Galligher explains. There is also some emerging evidence that changes in the way DNA is expressed during traumatic experiences may be literally passed on to children, Galligher says.

Children raised in families affected by intergenerational trauma have been found to be at greater risk of conditions such as anxiety and depression, and may be more likely to develop PTSD when exposed to their own traumatic events.

Intergenerational trauma, however, does not directly cause PTSD, Horsley says.

Symptoms: What Trauma Feels Like

A strong emotional response in the immediate aftermath of a traumatic event is not only normal, it’s to be expected, Naturale says. Many people will experience what she calls an “acute stress response,” so severe that they may become unaware of their surroundings or act out of character or inappropriately. The fight, flight, or freeze response, she says, will suppress the brain’s ability to think and function normally for a short period of time as a means of coping with a crisis.

This means the first few moments after a traumatic event tend to be chaotic, and individuals may not be able to remember everything they did or experienced during the event, Galligher says. But within a few hours, most people begin to experience intrusive thoughts associated with the trauma and find that they’re unable to stop thinking about what just happened.

“You distract yourself for a while, but you think about it again,” she says. “That’s going to continue,” she adds, but should start to diminish over the course of a few weeks.

This acute response, Galligher says, can cause:

Difficulty concentrating
Trouble relaxing
Struggling to fall or stay asleep
Intense emotions, like anger, anxiety, sadness, or shame
Emotional numbness
Feeling detached or estranged from others

Other immediate physical reactions to trauma can include:

Nausea or gastrointestinal distress
Sweating or shivering
Faintness
Muscle tremors or shaking
Elevated heart rate or blood pressure
Fatigue or exhaustion

Most survivors report that symptoms periodically return around significant milestones after the event, such as anniversaries. But for most people who experience trauma, initial symptoms subside after a few months to a year.

“It’s often a struggle to get through the first holiday or the first birthday [after a trauma] — after that, symptoms drop significantly,” Naturale says.

Naturale noted that in her experience working with survivors after 9/11, just sharing this information about normal responses to trauma significantly reduced the incidence of mental health symptoms.

Longer-Term Health Effects of Trauma

In some cases, a traumatic event may have longer-term implications, particularly if the trauma took place during childhood.

Children who are exposed to trauma may have a decreased sense of fear or pain and may have trouble processing sensory input, even though they are less likely than adolescents and adults to develop PTSD.

Adults may have trouble with attention and short-term memory, even when the new memories are not related to the trauma itself, because of changes triggered in the brain by the traumatic event.

These effects may improve with treatment.

Traumatic experiences may also be tied to physical symptoms, especially chronic sleep, gastrointestinal, cardiovascular, neurological, musculoskeletal, respiratory, dermatological, and urological problems. These symptoms may persist even after tests reveal no physical explanation. And longer-term emotional symptoms of trauma may include irritability or hostility, depression, mood swings, anxiety, grief, shame, and emotional detachment.

How to Cope With Trauma and When to Get Help

A common and healthy way to cope with trauma is to reach out to others to talk through and process what happened.

“The research shows that the two most important things after a loss are peer support and adaptive coping skills,” she says.

But not all social interactions are helpful. If an individual’s social network is not supportive and is dismissive of their experience and feelings, Horsley recommends the person find a safe place to talk — which may include therapy or a specialized support group for individuals with similar experiences. Many of these groups are available online, and many are open to survivors free of cost.

Healthy Coping Strategies

It’s important for survivors to give themselves permission to take additional time for self-care, and seek out fun activities that can give them a “break” from the intensity of their emotions, Horsley says. This means covering the basics by getting enough sleep, staying hydrated, and maintaining a good diet. But also looking for hope.

For example, Horsley say, if someone has experienced a significant loss, as she did, they might feel deprived of touch and closeness. A massage or acupuncture session may help fill this need. A new hobby or a class in an old interest might be just what’s needed — and activities involving movement such as yoga or dance may be especially helpful, Horsley says.

Many people find a new sense of meaning or purpose when they engage with healthy coping mechanisms, Horsley says. Additionally, attending memorials for the lost may fill a need to pay tribute to loved ones. Support groups can lead to new understanding or even advocacy.

Potentially Unhealthy Coping Strategies

Horsley cautions that not everything that technically qualifies as coping leads to positive outcomes. Comfort foods may help us get through a difficult time, for example, but excessive reliance on food as a sole coping mechanism may lead to other negative long-term health consequences. Similarly, Horsley says, individuals who turn to drugs and alcohol as a means of self-medicating for trauma are technically coping — but creating more problems for themselves down the road.

“Alcohol is a depressant; it will make you more sad and upset,” she says.

Social Support

Though healthy coping strategies can vary from person to person, social support is important for everyone, Naturale says. Isolation, unemployment, or a lack of access to supportive resources represent significant risk factors for developing mental illness following a traumatic event.

“Ninety percent of people get better in a reasonable amount of time with good social support and good coping,” she says.

If you’re coping with trauma, it may be beneficial to identify the people in your life you can turn to when you feel like you need to talk. These may be individuals with similar experiences, or who can otherwise help you feel seen and heard by validating your emotional response as a normal reaction to trauma, rather than dismissing your experience or suggesting the reaction is somehow inappropriate or disordered, according to Naturale and other experts.

If you’re unsure whether the people in your social network would be supportive, Naturale says, it never hurts to err on the side of caution and speak to a licensed therapist. A few educational sessions to focus on what to expect after trauma and how to cope may go a long way to promote recovery.

While she does not believe therapy is necessary for everyone who experiences a traumatic event, survivors should seek professional help if they feel as though they cannot connect with others and must isolate themselves; if they are experiencing thoughts of suicide; or if they find ongoing depression or anxiety is interfering with their day-to-day life months after a traumatic event, Naturale says.

If you are actively in crisis and need immediate support, call 911. You can also call the National Suicide Prevention Lifeline at 800-273-8255 or text 741-741 to reach a trained counselor with Crisis Text Line.

Editorial Sources and Fact-Checking

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All About Trauma: What It Is, Short- and Long-Term Effects, How to Cope With It, and When to Get Help