In a somber announcement from the New York City medical examiner’s office, it has been confirmed that the individual responsible for the fatal shooting of four people in a Midtown Manhattan office building this past July suffered from chronic traumatic encephalopathy (C.T.E.). This devastating degenerative brain disease is closely associated with repeated head trauma, commonly seen in contact sports like football.
C.T.E., a condition only diagnosable after death, was identified in the brain tissue of Shane Tamura, the gunman, who took his own life following the violent rampage at 345 Park Avenue.
A statement from the medical examiner detailed “unambiguous diagnostic evidence of Chronic Traumatic Encephalopathy, also known as C.T.E., in the brain tissue of the decedent.” The report noted that the findings indicated “low-stage C.T.E.,” aligning with established diagnostic criteria.
Tamura, a former high school football player, tragically ended his own life with a self-inflicted gunshot wound to the chest after the attack. He left behind a chilling note articulating his rage towards the National Football League, accusing the organization of intentionally obscuring the severe impacts of C.T.E.
Police reports indicate that Tamura, 27, traveled from his Las Vegas apartment to Manhattan, specifically targeting the building at 345 Park Avenue, which houses the NFL headquarters. This address tragically became the site of the shooting spree that claimed five lives, including his own.
Excerpts from Tamura’s note, released by the police, further condemned the National Football League, asserting that it prioritized profits over player safety by concealing the dangers inherent in the sport.
Tamura’s family chose not to comment on Friday’s findings.
The posthumous diagnosis of Tamura’s brain condition reignites critical questions regarding the potential long-term risks of playing tackle football, even at the youth level.
Tamura, whose football career did not extend beyond high school, had a note referencing C.T.E. and alleging that the NFL intentionally hid the risks of brain trauma for financial gain. Authorities believe he sought vengeance against the league, whose headquarters are located in the targeted building.
Over the past two decades, numerous former football players, boxers, and hockey players have been diagnosed with C.T.E., leading to heightened awareness of the sport’s dangers and increased research into the disease and its symptoms. Despite this, leaders of the NFL and other athletic leagues have largely been reluctant to fully acknowledge the direct correlation between their sports and brain trauma.
C.T.E. frequently impacts the superior frontal cortex, a brain region vital for cognitive functions and executive control, including working memory, planning, and abstract reasoning. The disease also commonly affects the amygdala, crucial for emotional regulation, aggression, and anxiety. Typical symptoms encompass difficulties with aggression and impulse control, varying degrees of dementia, mood instability, poor judgment, and disorganized behavior.
Most diagnosed cases of C.T.E. have involved former athletes who endured 15 to 20 years in contact and collision sports like football, likely accumulating thousands, if not tens of thousands, of head impacts throughout their careers. Researchers caution, however, that C.T.E. studies are prone to selection bias, as most families who donate loved ones’ brains do so because symptoms were present.
As understanding of the disease deepens, more families have donated the brains of younger athletes, some of whom have also shown evidence of C.T.E., though typically in less severe forms than in older individuals. At 27, Tamura is now part of this growing demographic.
Regardless of age, researchers remain cautious about directly linking C.T.E. to specific actions, particularly murder or suicide, as many other factors could influence such complex decisions.
Dr. Ann McKee, director of the Boston University C.T.E. Center, who has examined thousands of brains from athletes, soldiers, and others with brain trauma, notes that the connection between violent, impulsive behavior and C.T.E. is still not fully understood, emphasizing the need for further studies.
“Damage to the frontal lobes can impair decision-making and judgment,” Dr. McKee recently explained to The Times. “It may also trigger impulsive and aggressive behaviors, suggesting a potential link between brain injury and such actions.”
Several high-profile incidents involving former football players committing violent crimes have drawn significant national attention, most notably Aaron Hernandez, the former New England Patriots tight end. Hernandez was convicted of murder and subsequently died by suicide in prison at age 27, with his brain revealing a form of C.T.E. so severe it was comparable to that seen in players in their 60s.
Phillip Adams, who fatally shot six people before taking his own life in Rock Hill, S.C., in 2021, was also found to have an “unusually severe” form of C.T.E. He was 32 and had played six seasons in the N.F.L.
Other former N.F.L. players who died by suicide, such as Dave Duerson, intentionally shot themselves in the chest to preserve their brains for study. Duerson explicitly requested that his brain be examined for C.T.E.
However, researchers emphasize that these extreme cases do not necessarily represent the broader population of individuals living with C.T.E.
“I would never draw a direct line between someone’s brain pathology and any specific violent act, because the majority of people who have C.T.E. never committed anything like this,” Dr. Daniel H. Daneshvar, chief of brain injury rehabilitation at Harvard Medical School, recently told The Times.
For a long time, the risk of developing C.T.E. was thought to be confined to those who endured years in professional contact sports like football, rugby, or boxing, suffering countless blows to the head. However, more recently, the disease has been diagnosed in younger athletes across various contact sports, some of whom never played professionally or even at the collegiate level.
A 2023 Boston University study examined the brains of 152 contact-sport athletes who passed away before age 30, whose families had expressed concerns about brain disease. Over 40 percent of these athletes exhibited evidence of C.T.E., with most having played no higher than high school or college. Out of the 63 individuals diagnosed with C.T.E. who died young, 48 had played football.
These younger athletes, similar to older ones, showed deposits of the tau protein—a hallmark of C.T.E.—in specific brain regions. However, the tau protein concentration was lower than in older athletes, and the cognitive symptoms observed in these young individuals were similar to those in other youth athletes without C.T.E. This raises questions about whether the smaller amount of tau directly caused their symptoms, suggesting other contributing factors might be involved, according to researchers.
“The message here is that there’s less scientific understanding of what’s driving the symptoms in these younger players, and whether it’s related to brain trauma or perhaps other things,” stated Gil Rabinovici, a professor of neurology and radiology at the University of California, San Francisco, who is currently developing imaging techniques to diagnose dementia and C.T.E. in living patients. “It’s going to be important to look at other brain changes that are not tau related. We should be very cautious in trying to attribute their behavior to what we find in the brain.”
Without a definitive test for C.T.E. in living individuals, athletes, much like Tamura, might attribute their cognitive struggles to the disease. Dr. Rabinovici referenced a survey of 4,180 former professional football players, where 34.4 percent believed they had C.T.E. based on symptoms like headaches, cognitive difficulties, depression, and suicidal thoughts.
Tamura was prescribed medication for anxiety, depression, and bipolar disorder, as confirmed by his mother and New York police officials. He meticulously penned suicide notes that underscored his fixation on brain injuries. He firmly believed his deteriorating mental health was a direct consequence of playing football and enduring repeated head impacts.
Dr. Rabinovici and his fellow researchers have been dedicated for years to developing a diagnostic test for C.T.E. in living patients. Promising avenues include blood tests and brain imaging techniques capable of identifying the tau protein in specific areas of the brain. He described progress on a solution as “slow and steady.”
Following years of public relations challenges and mounting evidence linking football to C.T.E., the NFL’s highest health and safety official publicly acknowledged the connection in 2016. Since then, the league has actively encouraged children to move away from conventional tackle football, advocating for safer tackling techniques and promoting flag football instead.