NFL star Junior Seau had brain disease linked to football-related head trauma

The late NFL star Junior Seau suffered from a debilitating brain disease linked to football-related head trauma, his family and researchers told ABC News.

"What was found in Junior Seau's brain was cellular changes consistent with CTE [chronic traumatic encephalopathy]," said Dr. Russell Lonser, chairman of the Department of Neurological Surgery at Ohio State University.

[Patients with CTE suffer from] "impulsivity, forgetfulness, depression, [and] sometimes suicidal ideation," Lonser added.

Seau, who committed suicide in May 2012, experienced mood changes and depression before he died, said his ex-wife, Gina Seau, who said Junior suffered from depression insomnia in the months before his death.

The startling results of the blind National Institutes for Health's study on Seau's brain (researchers were not told the brain they were analyzing was his) bolsters the claims made by NFL widows and other pro athletes that repeated concussions and hits to head can lead to dementia, depression and suicide.

So far, more than 30 NFL stars have been posthumously diagnosed with CTE, which can only be diagnosed through an extensive post-death probe of the brain. And last year, over 4,000 former NFL players filed a federal lawsuit alleging the NFL deliberately concealed evidence of the link between football-related head injuries and long-term neurological damage.

While the NFL has repeatedly denied the allegations, the recent shocking suicides of several high-profile NFL stars, including Junior Seau, Dave Duerson, and Ray Easterling (as well as MLB star Ryan Freel) has shone a spotlight on the devastating impact of CTE.

The Seau children have all stopped playing football following their dad's tragic suicide. "It's not worth it for me to not have a dad," said Tyler Seau, 23. "So, to me, it's not worth it."

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