John Frechette
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'Brain changes' seen in American football players

Some teenagers appear to show changes in their brains after one season of playing American football, a small study suggests.

You don't have to be a seasoned professional player to suffer from the effects of repeated bouts of concussion.

John Frechette's career in sport was a short one, but his family believes he suffered the effects for the rest of his life.

Alex South reports from Boston.

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