Updated

At his darkest moments a few years ago, when the pain in his head was just about too much to bear, former Chicago Bears quarterback Jim McMahon thought about killing himself.

If he kept weapons at home, he says, he is "pretty sure I wouldn't be here."

McMahon discussed his struggles with early onset dementia and depression Tuesday, issues that he believes were brought on by the beating he absorbed playing football. He is scheduled to be honored Wednesday in Chicago by the Sports Legacy Institute, a Boston University-based group that has been studying the effects of brain trauma in athletes and others.

While the suicidal thoughts are a thing of the past, the fight with dementia continues. He is also digging in for a battle with the NFL.