Mass Violence: What We Know, and What We Need to Learn

Lloyd I. Sederer, MD; Jeffrey A. Lieberman, MD


July 31, 2019

Editorial Collaboration

Medscape &

Editor's note: This video was recorded prior to the recent and tragic shootings in El Paso, Texas, and Dayton, Ohio.

This transcript has been edited for clarity.

Lloyd I. Sederer, MD: Welcome. I'm Dr Lloyd Sederer at Columbia Psychiatry, reporting for Medscape. Today, our guest is Dr Jeffrey Lieberman, chairman of the Department of Psychiatry and professor at Columbia. Our topic is going to focus on mass violence and some of the long-term consequences for survivors on their lives and on their biology. Jeffrey, welcome.

Jeffrey A. Lieberman, MD: Thanks very much, Lloyd. It's good to talk with you.

What Is Mass Violence?

Sederer: Teach us about mass violence. How is it defined? How do we understand what is going on in these instances?

Lieberman: Mass violence is very specifically defined as violence perpetrated against more than three or four individuals. Often, it's often committed against random strangers—people who are not known [to the perpetrator]—and there may be no specific rhyme or reason to it. It can occur in a public setting and any type of venue, not necessarily in a home or in a place of crime. It's a particularly pernicious kind of crime. Despite the fact that it's shocking to the public, it's widely portrayed in the media, and it has effects that resonate on its victims for a long period of time.

It only accounts for a small amount of all violent crime. But it's such a random, senseless, and horrifying type that it has consequences way beyond the specific numerical loss of life.

Sederer: Its randomness is part of what is so unsettling for everyday people. You don't know when this could happen. It's different in that respect from domestic violence or being in a tough neighborhood.

Lieberman: It's really the civilian or domestic equivalent of terrorism, because its shock value often exceeds the loss of life. But, pertaining to Columbia Psychiatry and ourselves as psychiatrists, the relevance is twofold.

People with mental illness account for a very small proportion of violence in our society—4% or less of all violent crimes are perpetrated by people with mental illness. However, people with mental illness disproportionately perpetrate mass violent crimes. These situations occur largely when individuals suffering from a very small number of diagnoses (ie, psychotic conditions, a mood disorder, posttraumatic stress disorder [PTSD], or a condition aided and abetted by substance abuse) are untreated or ineffectively treated. These people are impelled by their symptoms, as opposed to being motivated by [their desire to] steal money, settle a grudge, or engage in some kind of organized crime or gang warfare, for example.

The effect that it has on people is so pernicious, not just the people that get injured as a result of it, but those that are in proximity and family members of the individuals who are affected by it. They all suffer the consequences in the form of experiential trauma.

Impact of Mass Violence

Sederer: One thing I've learned in my work is that the impact of a disastrous event, whether it's a natural disaster or mass violence, is highly related to your proximity to the event or to the person, so people who witness these events and people who are related to other people who are victimized—or close friends and relatives. What about the general public? Is there such a thing as PTSD for the general public after a mass violent episode?

Lieberman: Not really. It's like watching a horror movie. You are affected by it, and you may have some lasting thoughts about it when you come out of the theater, but it's not usually that intense, distressing, or disabling.

Three variables determine the effect of a traumatic event on an individual. One is how intense the event is. Was the patient in an earthquake, terrible fire, auto accident, theater of war, firefight, or mass violent incident, for example? Second is proximity to the event. The third thing is inherent resilience or susceptibility, because some people are able to basically shake this off without any kind of lasting effects whereas others are indelibly altered for weeks, months, years, or even the rest of their lives.

Effects of Trauma on Psychology and Biology

Sederer: Recently, there were three suicides: two people who had witnessed the Parkland, Florida murders and a father of one of the children at Sandy Hook. How do we understand those long-term consequences of a disaster? Teach us about what is happening in the psychology and biology of that person.

Lieberman: The public may be affected even if they were not in immediate proximity, because the media reifies the effects of a mass violent incident. That pertains to why you may find delayed consequences occurring, and also the fact that the consequences can be distributed far and wide from an instant.

The father of a victim of Sandy Hook, Connecticut, is responding to an incident that occurred in Florida. Why? Because the cognitive information about what was going on in Florida reactivates the emotional trauma that they had. This is really the pathophysiology of trauma, which has been a terribly understudied and underemphasized psychopathologic condition.

It's hard for people to appreciate this. When you get injured (eg, twist an ankle, bump your knee and get a bruise, get an infection), everything has a physical cause, so how can something that is intangible have a deleterious effect? That is because the brain is this marvelous organ that is susceptible to it. The brain is very resilient in being able to manage all the stresses, challenges, and vicissitudes of daily life, and when you have to meet demands and so forth, it is able to reequilibrate. But it has its limits.

Sederer: Help our viewers understand what has changed in the brain for those who suffer the trauma but are not resilient.

Lieberman: They are perceiving sensory stimuli that describe the experiences they are having, and they process it in the brain. And if it's deemed important enough to store in terms of long-term memory, it's encoded in the hippocampus in the form of a protein. Those experiences where there is an emotional component are also encoded. When the experiences of such emotional intensity become overwhelming, it's difficult for it to be contained in a way that is outside of consciousness. You can't have in forefront of your mind all the things you have ever done in your life, so you have to store it away and just retrieve it whenever you need it. But if some things are just so intensely emotional and distressing, they can't readily be controlled in the same way. The process by which this is intended to be done this through the frontal cortex exerting what's called cognitive control over subcortical structures and in this case, the medial temporal lobe, hippocampus, and amygdala.

The events with these intense disturbing emotions are things that pervade into consciousness and can't be put out of mind and induce distressing effects, whether they be hypervigilance, anxiety, anger, or so forth. Apart from avoiding massive experiential trauma, how can you treat that?

Managing Effects of Trauma

Sederer: This has to do with some of the work focusing on the triggers to that emotional reactivity using cognitive behavioral therapy (CBT) and medications. Can you say a little bit about effective approaches to a persistent trauma?

Lieberman: We do a terrible job at managing the effects of traumatic experiences. Think about how much public health has advanced (eg, sanitation, no smoking in public places, nutrition, exercise). It's terrible because we do nothing to manage [effects of traumatic experiences]. We have treatments that are sensibly used for people with PTSD, whether it's medication, desensitization, or CBT. These are minimally to moderately effective at best.

A really intensive and enlightened effort should have begun in the Department of Defense and the military to study the experience of trauma. If you are in war, you are not going to get away from that. But are there things you can do to immunize people against the effects of intense experiential trauma? If they have been in a firefight, or they are really shell-shocked or traumatized, can you do something to disrupt that before the event is translated encoded into long-term memory? If it's too late and already encoded, then you've got to figure out a way to desensitize it or relieve it.

Progress in military medicine has been miraculous. People who used to die in the battlefield from wounds now are saved. They have medics and field hospitals. Patients are transported to Germany, and to Walter Reed National Military Medical Center, if they need to. What do you do for experiential trauma?

Sederer: This is where the field needs to go in terms of what you call immunization, or the protecting of people against the effects of life threatening-exposure, and early intervention, or identifying those who are at risk and helping them not make this permanent part of their life.

Lieberman: It's not just the military. It's first responders, fire, police, victims of muggings or accidents. When you come to an emergency department and they minister you your physical injuries, do they minister your psychological injuries? The amount of research focused on developing these interventions at all these different stages is minimal. Probably the two conditions in the Diagnostic and Statistical Manual of Mental Disorders that are most validly modeled in nonhuman species, such as rodents, are trauma and addiction. Some of our faculty, Christine Ann Denny and Rene Hen, have been focusing on a line of research. They can model trauma and PTSD with fear conditioning, and then use different pharmacologic manipulations to see whether you can inhibit the consequences of fear conditioning...

Sederer: ...before it sets in firmly and persistently. Thank you for teaching us so much about this and about the work that your department is doing in terms of making things better in the future.

Thank you for joining us. I'm Dr Lloyd Sederer, here at Columbia Psychiatry, reporting for Medscape.

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