Videos CNN’s Dr. Sanjay Gupta explains the physiology of concussions and the long-term effects of suffering one. Articles You May Like Russia accused of escalating hybrid attacks in Europe after telecoms cables cut Former Labour deputy prime minister John Prescott dies Fastest-Moving Stars in the Galaxy May be Piloted by Aliens, New Study Suggests Kanye West accused of sexual assault on set of music video in new lawsuit Elliott named most popular for 7th straight year