Brain Exams Aim to Predict Who Is at Risk of Committing Murder

An NBC Bay Area investigation details first-of-its-kind research that found detecting abnormalities in the brain may help identify who might be at risk of committing violent attacks in the future

Cutting-edge research is revealing new ways to potentially prevent violent acts, including mass shootings, years before the thought of violence ever crosses the minds of murderers. 

A study of roughly 1,000 prisoners revealed across-the-board brain abnormalities in those who committed homicide, leading researchers to believe such behavior, if identified early enough, can be quashed with therapy and medication.

The findings come in the wake of several recent mass shootings across the country – seven dead in Odessa, Texas; 22 shot and killed at a Walmart in El Paso, Texas; and three people, including two children, killed by an active shooter at the Gilroy Garlic festival.

Researchers have linked such violent behavior to abnormalities in the brain, and believe early detection may help identify who might be at risk of committing violent attacks in the future.

"I think we're getting there in terms of finding areas of the brain that may explain homicidal behavior," said Dr. Hannes Vogel, the director of Neuropathology at Stanford University.

Vogel sideview see face
NBC Bay Area
"I was involved in the examination of Steven Paddock's brain, the mass murder from Las Vegas," said Dr. Hannes Vogel, a Neuropathologist at Stanford University. Vogel has studied thousand of brains over the past three decades.

'The [Brain] was Hand Delivered to Me'

On a typical day in his laboratory, Vogel dissects brains in search of tumors and diseases. Two years ago, however, he was pulled into a criminal investigation following the Las Vegas mass shooting that left 58 dead and hundreds injured. The Las Vegas County coroner sought his help in examining the brain of the mass shooter.

"I happened to be on a speaking engagement in Europe and got a call in the middle of the night, and they said they wanted to send me the brain, and it was hand delivered to me," Vogel said. 

The brain belonged to Stephen Paddock, 64, the suspected shooter in Las Vegas.  

"I was asked to diagnose and rule out certain disease processes that might have contributed to his behavior," Vogel said.

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NBC Bay Area
Brains are typically placed in a diluted formaldehyde solution and shipped to Dr. Vogel's lab in buckets. "I happened to be on a speaking engagement in Europe and got a call in the middle of the night and they said they wanted to send me the brain," said Vogel, referencing the request to examine the brain of mass murderer Stephen Paddock.

Dissecting the Brain of a Mass Killer

He set out to conduct the examination the same way he began any of the thousands of other dissections he has undertaken during his career.

"I would take a scalpel and cut out a portion of the brain, and that ultimately ends up as a slice on a microscope slide with special stain that I look at under the microscope,” he said.

NBC Bay Area
Thin slices of brain - about 1/20th the thickness of a human hair, are prepared for viewing on a microscope slide.

Unusual Amounts of Scarring Found in Brain of Las Vegas Mass Shooter

"[Paddock] took his own life with a bullet wound to the to the back of the brain, but it still left a considerable amount of the brain that was amenable to examination," Vogel said.

In the shooter’s brain, Vogel found large amounts of what can be described as a type of scarring of the brain tissue. The scientific term for it is corpora amylacea. These large, complex molecules accumulate in the brain during the aging process and can be present with various brain diseases, including Alzheimer’s and Parkinson’s. What stood out to Vogel was how much was found.  

"The quasi-scarring process in the brain was higher than the average 60-something-year-old male," he said. 

NBC Bay Area
Investigative Unit Photographer Mark Villarreal captures the brain images that Dr. Vogel sees in his microscope.

Inmate Brain Testing Set Out to Demystify Minds of Murderers

It's worth noting that Vogel found this condition on areas of the brain that are responsible for decision-making, emotion and anger. The corpora amylacea, however, is not well understood in neuroscience, and Vogel was unable to draw any connection to the shooter's behavior. 

"The significance of it is totally unknown," he said. 

More than 1,000 miles away, in another lab at the University of New Mexico in Albuquerque, research inside prisons is revealing even more about the minds of murderers.

“Prevention – that is the ultimate goal,” said Dr. Kent Kiehl, neuroscientist and psychologist at the Mind Research Network. 

Keihl, a professor at the University of New Mexico, set out with his team to scan the brains of murderers. To do that, they built a mobile MRI brain scanner, fitted it into a large truck and drove the machine across the county to 10 prisons.

"The prisoners are very happy to participate in the research, " Kiehl said.  “That gives them an opportunity to interact and talk with an expert ... who is going to give them a chance to confidentially talk about all their problems and issues which they may not want to share with anybody else."

Mind Research Network
Dr. Kent Kiehl and his team built a mobile brain scanning truck, which they drove to ten prisons in New Mexico and Wisconsin.

Brain Scans Conducted on Nearly 1,000 Inmates 

In the last decade, the team has scanned the brains of 998 prisoners. The findings show the brains of killers stand out significantly compared to the rest of the population. 

"There are regions of the brain in individuals who've committed a homicide that truly are different than … their peers," Kiehl said.  

His latest study, released this year, shows specific sections of the brain, responsible for controlling emotions, impulses and social awareness, are less developed among those who have killed someone.

"We're finding for the first time that they are quite different," Kiehl said. “So now, it's a question of how did they get that way? How might we understand this information?" 

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Courtesy of Family
After scanning the brains of murderers, Dr. Kent Kiehl of the University of New Mexico said, "They're pretty reliably different - surprisingly different."

Are Murderers Born with Violent Tendencies?

Kiehl believes people are born with those brain differences and says therapy or even medicine can physically transform the brain to reduce the risk of dangerous behavior.

"We're going to try to implement treatments that we know work on those systems of the brain. Then we would hopefully see changes that would prevent these types of things from ever happening," he said. He believes learning a skill like juggling or a foreign language may, in some cases, be enough to rewire the deficient circuits of the brain.  

There are potential ethical hurdles in identifying patients, including children, as having a predisposition for violence. Kiehl, however, said he is already receiving requests from parents, around the country and abroad who want their kids tested. The scans and analyses run about $10,000 per child, but it could very well be years before this type of testing becomes widely available in the Bay Area or at other medical centers across the country.

“I really do believe that it will be helpful for developing treatments for developing things that would be relative to prevention,” Kiehl said.  “That’s really the ultimate goal of the work.”


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