IBF light heavyweight champion Bernard Hopkins, and UFC light heavyweight champion Jon Jones, went face to face during a press conference held on Tuesday at the US Capitol in Washington, DC to discuss the Professional Fighters Brain Health Study by the Cleveland Clinic, located in Las Vegas. Several organizations have pledged $600,000 to the facility for the study. The study is going to deal with developing methods to detect early and subtle signs of brain injury and chronic neurological disorders. Among those present at the press conference, Senate Majority Leader Harry Reid, Republican presidential nominee and Arizona Senator John McCain, IBF light heavyweight champion Bernard Hopkins, WBO super featherweight champion Mikey Garcia, UFC champion Jon Jones, and several others. Photo by Malki Kawa.