The NFL and the players' union announced a series of changes Friday to the way potential concussions are handled during games following an ugly incident in which Texans quarterback Tom Savage was allowed to return to the field after a hit left him on the ground, arms shaking.

The brains of 99 percent of former National Football League players showed signs of a disease linked to repeated hits to the head that can lead to aggression and dementia.

One-third of the world’s dementia cases could be prevented, a new report is warning. Do you know your risk factors for dementia?