Car Accident CTE Injuries

The connection between repeated head trauma and long-term brain disease was not widely accepted until NFL research forced it into the open. The timeline spans more than two decades.

2002-2005

Dr. Omalu’s Discovery

Forensic pathologist Dr. Bennet Omalu examined the brain of Pittsburgh Steelers center Mike Webster and discovered abnormal tau protein deposits. He published his findings in Neurosurgery in 2005.

2005-2009

NFL Denial

The NFL’s Mild Traumatic Brain Injury Committee disputed Omalu’s findings. In 2009, Congressional hearings compared the NFL’s response to the tobacco industry’s denial of cancer risks.

2012

Junior Seau

Former San Diego Chargers linebacker Junior Seau died by suicide. The National Institutes of Health confirmed CTE in his brain tissue.

2015

NFL Settlement

The NFL agreed to a settlement fund exceeding one billion dollars for former players diagnosed with neurodegenerative diseases linked to repeated head trauma.

2017

Aaron Hernandez

Former New England Patriots tight end Aaron Hernandez was diagnosed posthumously with Stage III CTE at age 27, one of the most severe cases ever found in someone that young.

2023

BU CTE Center Study

A study led by Dr. Ann McKee at Boston University found CTE in 345 of 376 former NFL players examined, a rate of 91.7%.

CTE Brain Changes

CTE is caused by abnormal accumulations of phosphorylated tau protein in the brain. Tau protein normally stabilizes brain cell structure. After repeated impacts, tau proteins become misfolded and clump together, killing surrounding brain cells. The disease progresses through four stages.

Research published in Science (2025) from Harvard Medical School and Boston University found that CTE involves DNA damage similar to Alzheimer’s disease, with immune system activation playing a key role in determining who develops the disease after repeated impacts.

Brain Trauma Research For Car Accident Victims

CTE is not limited to professional athletes. The Boston University CTE Center has documented CTE in individuals with head trauma from military service, intimate partner violence, and other non-sports sources. The mechanism is the same: repeated impacts to the brain cause progressive tau protein accumulation.

Car accidents produce significant forces on the brain. A rear-end collision at moderate speed generates enough force to cause a concussion, even when the occupant is restrained. For someone who has had a prior concussion from any cause (sports, a fall, a previous crash), a new impact compounds the damage.

Second-impact syndrome occurs when a person sustains a new concussion before fully recovering from a prior one. The brain swells rapidly and the results can be catastrophic. Even without full second-impact syndrome, cumulative brain trauma from multiple concussions over a lifetime creates compounding risk that no single event captures on its own.

A BU-led study found that individuals with repetitive head impact exposure showed an average 56% loss of certain frontal neocortex neurons, along with vascular dysfunction and inflammatory responses, even without the classic tau protein markers. Both sub-concussive impacts and diagnosed concussions can drive this damage.

CTE Evidence In A Car Accident Claim

If you had a prior concussion and a car accident caused another brain injury, the cumulative effect matters. A traumatic brain injury that might have resolved in weeks for someone with no prior history can produce lasting cognitive problems for someone with a history of head trauma.

Insurance adjusters treat each crash as an isolated event. They do not account for cumulative brain trauma. They will argue that your current symptoms are from the prior injury, not the crash. The medical research tells a different story: each new impact adds to the total damage, and the crash that pushes someone past a threshold is fully compensable.

Why Concussions Are Not Minor Injuries

A concussion is a traumatic brain injury. The idea that a concussion is “just getting your bell rung” is exactly the thinking the NFL used for decades before the science forced a reckoning. The same research that changed how the NFL treats head injuries applies to car accident victims. Every concussion matters. Every impact adds up.

At Sam Aguiar Injury Lawyers, we work with neurologists and neuropsychologists who understand cumulative brain trauma. The full history of head impacts, along with the current injury, provides necessary context for the case, because that context is what makes the case.