Big Tobacco is the name used to describe the largest tobacco companies as a singular group. The name became commonplace in the 1990s when major tobacco companies were called before Congress to answer charges that they had known of the link between smoking and lung disease all along, despite claiming that such scientific evidence did not exist. Throughout League of Denial, a comparison is made between the cover-up by Big Tobacco in the 1990s and the way in which the NFL handled its concussion crisis. 

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease caused by repeated head injuries. Bennet Omalu discovered the disease in 2002 during the autopsy of Hall of Fame center Mike Webster. Since that time, over 100 former NFL players have been found to have CTE. The disease is similar to Alzheimer’s disease and dementia pugilistica, which is commonly found in the brains of boxers, because it involves the buildup of tau protein in different regions of the brain.

League of Denial offers two specific definitions of a concussion, one from the NFL’s Mild Traumatic Brain Injury Committee and one from neuroscientist Kevin Guskiewicz. The MTBI committee’s definition is rather broad, calling it “any traumatically induced alteration of brain function” and listing the symptoms of blackouts, wooziness, amnesia, headaches, vertigo, memory loss, personality change, and lethargy (132).