In a tragic incident that has reignited the national conversation about brain health in contact sports, the New York City medical examiner confirmed that Shane Tamura, the gunman who killed four people in a Midtown Manhattan office building in July 2025, suffered from chronic traumatic encephalopathy (CTE)—a degenerative brain disease linked to repeated head trauma .
Who Was Shane Tamura?
Tamura, a 27-year-old former high school football player from Las Vegas, targeted 345 Park Avenue—the headquarters of the National Football League (NFL)—on July 28, 2025 . After fatally shooting four individuals and wounding another, he took his own life. A handwritten note found on his body expressed anger toward the NFL, which he accused of concealing the long-term dangers of CTE. He specifically requested that his brain be studied for signs of the disease .
What Is CTE?
Chronic traumatic encephalopathy is a progressive neurodegenerative condition caused by repeated blows to the head. It can only be definitively diagnosed after death through postmortem brain tissue analysis .
According to the medical examiner, Tamura’s brain showed “unambiguous diagnostic evidence” of low-stage CTE, consistent with current consensus criteria .
Common Symptoms of CTE
- Memory loss and confusion
- Mood changes, including depression and irritability
- Erratic or aggressive behavior
- Suicidal thoughts or actions
- Difficulty with planning, decision-making, and concentration
The Four Stages of CTE
CTE progresses through four distinct stages, each marked by worsening symptoms and brain pathology:
| Stage | Key Characteristics |
|---|---|
| Stage I | Mild headaches, attention issues, mood swings |
| Stage II | Depression, short-term memory loss, impulsive behavior |
| Stage III | Cognitive decline, executive dysfunction, increased aggression |
| Stage IV | Severe dementia, speech and motor impairments, profound memory loss |
Tamura’s case was classified as low-stage CTE, likely Stage I or II .
CTE and the NFL: A Troubled History
The NFL has faced mounting criticism for decades over its handling of head injuries. Boston University’s CTE Center has found evidence of the disease in 345 of 376 deceased former NFL players studied—nearly 92% .
While the league has implemented new concussion protocols and rule changes, critics argue these measures are insufficient, especially for youth and high school athletes who lack access to advanced medical care.
Recent Advances in CTE Research
In 2025, researchers at Boston University launched a $15 million study aimed at diagnosing CTE in living patients—a breakthrough that could transform prevention and treatment .
A September 2025 study also revealed that brain damage from repetitive head impacts may begin years before CTE pathology is detectable, suggesting the need for earlier intervention in young athletes .
💡 Key Insight: CTE is no longer seen as exclusive to professional athletes. High school and even middle school players are now considered at risk due to cumulative subconcussive hits .
Victims of the July 2025 Shooting
- Didarul Islam – NYPD officer
- Aland Etienne – Security guard
- Wesley LePatner – Senior executive at Blackstone
- Julia Hyman – Employee at Rudin Management
- Craig Clementi – NFL employee (wounded)
What’s Next for CTE Awareness?
Advocates are calling for:
- Stricter regulations on youth contact sports
- Mandatory brain health screenings for high-risk athletes
- Greater transparency from sports leagues about long-term risks
- Increased funding for CTE research and prevention
For more on how brain injuries affect young athletes, see our in-depth guide: [INTERNAL_LINK:youth-sports-brain-injuries].
Learn more about ongoing CTE research from the Boston University CTE Center, a leading authority on the disease.
Sources
- https://www.nytimes.com/2025/09/26/us/cte-football-tamura-gunman.html
- https://www.bu.edu/cte/
- https://www.cdc.gov/traumaticbraininjury/cte/index.html
- https://www.nature.com/articles/s41591-025-02678-9
