-- In order to receive a concussion, some form of trauma must be administered to the skull to knock the brain about within and briefly off of its state of leverage, causing bruising, possible nerve damage and often the damaging of brain cells.
According to Brett Favre, that exact gruesome instance may have occurred over a thousand times throughout his 20-year NFL career.
The former Green Bay Packers quarterback and NFL Hall of Fame member was on NBC's "Megyn Kelly Today" last week discussing the topic in part due to his open advocacy for concussion research.