In May 2011, scientists announced that an autopsy of the brain of former Chicago Bears safety David Duerson, 50, who died from a self-inflicted gunshot wound, showed evidence of "moderately advanced" chronic traumatic encephalopathy, or CTE.

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He felt his worries were founded when he learned that star NFL linebacker Junior Seau -- who took his own life last May -- suffered from a neurodegenerative brain disease that can develop from concussions known as chronic traumatic encephalopathy or CTE.

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Research, such as a study done by Boston University School of Medicine, has identified serious brain damage, or CTE -- chronic traumatic encephalopathy -- not only in the autopsied brains of professional football players but in at least one high school player's brain as well.

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According to the guidelines, not participating in contact sports (to avoid concussions) is the only modifiable way to reduce risk for future cognitive decline or potentially CTE in older athletes with multiple prior concussions.

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It could save lives and provide families of athletes a degree of emotional stability, since symptoms of CTE may appear within months or many decades after the trauma.

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The time has passed for casting blame on what precautions were or were not taken to prevent concussions and CTE.

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The authors also point out that the severity of their CTE was tied to how the individuals had played football, which suggests that CTE is more likely to occur as a result of repeated mild injuries, rather than one or two severe ones.

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