CTE: If Seau Suffered From it, He Wouldn't Be the First

What caused Seau's death?

Today the sports world was rocked by the death of NFL legend Junior Seau, and the apparent cause of his death is giving many fans and players cause for concern.

Seau died of an apparent suicide, leading many to immediately begin speculating as to if this has anything to do with depression, related from concussions that Seau may have incurred during his career. While the linebacker didn't have a history of concussions, he was known to give them out throughout the 20 seasons he spent as a player in the league.

In the last two decades several former NFL players have been diagnosed with chronic traumatic encephalopathy (CTE), a disease discovered by Boston University researchers from examining the brains of deceased athletes. Those who suffer from CTE — which currently can be diagnosed only postmortem — can suffer from depression, the loss of impulse control, memory loss and, in late stages, dementia. The disease is believed to arise from repeated blows to the head and concussions that naturally occur in the physical, nearly violent game of football.

Neurosurgeon Julian Bailes, chairman of the Department of Neurosurgery at the NorthShore University HealthSystem in Chicago, told USA Today, "We don't have any strong evidence (yet about Seau), and we know that people commit suicide for other reasons. … But to me it's also concerning due to the fact that he had such a long playing history."

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If it is proven that Seau was suffering from CTE, he wouldn't be the first player to take his own life to end as a result of it. These three players are all suspected to have suffered from the condition.

Dave Duerson

Duerson was a former NFL safety who played in the league for 10 years and committed suicide last year at the age of 50.

The former Chicago Bears player killed himself in the same manner as Seau — with a gun. Before his death, Duerson sent a text message to his family saying that he wanted his brain to be examined after his death at the Boston University School of Medicine. The school was the first to discover the CTE disease and its fatal effect on athletes.