A new study released on Monday suggests that years of head trauma from football or other contact sports lead to a distinct pattern of brain damage, from athletes having trouble focusing to aggression and dementia.
Researchers examined the brains of 85 former athletes and soldiers who sustained multiple mild head injuries over their lives and discovered the condition they developed, chronic traumatic encephalopathy, came in an “ordered and predictable” four-stage pattern.
The condition, which causes depression and erratic behavior, has attracted public concern in recent years following the grisly, high-profile suicides of former professional athletes.
Published in the journal Brain by researchers affiliated with Boston University School of Medicine, the latest study explains how the condition progresses through four stages that can begin with mild memory loss, progress to cognitive failure and eventually bring on aggression.
Symptoms of stage one CTE include headache and loss of attention following depression, outbursts of anger and short-term memory loss in stage two. Those in stage three encounter executive dysfunction and cognitive impairment. Symptoms of the most severe fourth stage include dementia, aggression and difficulty finding words.
Researchers are now able to chart CTE’s progression in the brains of dead people who had suffered from the condition originally known as “dementia pugilistica” for its occurrence in boxers but are unable to diagnose it in the living.
“Until we do that, we can’t fully understand the risk factors, we can’t understand how common it is,” said Robert Stern, a Boston University professor and co-author of the study.
On Saturday, Kansas City Chiefs linebacker Jovan Belcher shot and killed his girlfriend and then shot himself in front of the team’s coach and general manager in a horrific suicide that shocked fans of the National Football League.
There was no evidence Belcher’s actions were related to brain injury.
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