Thomas Jones on concussions: It's scary to think about what causes me to forgetOn SI Now, former NFL running back Thomas Jones discusses why he wants to donate his brain to research and what motivated him to start acting.SI Staff|Share on FacebookShare on XAdd us on On SI Now, former NFL running back Thomas Jones discusses why he wants to donate his brain to research and what motivated him to start acting.Published Jan 14, 2015SI STAFFShare on FacebookShare on XHome/NFL