This Is Your Brain on Mixed Martial Arts

Michael Bisping has fought professionally in mixed martial arts since 2004. Last year, the journeyman won his first title. He knocked out Luke Rockhold in the first round to win the middleweight belt in the Ultimate Fighting Championship, or UFC, the most popular of several MMA organizations. On Nov. 4 of this year, at age 38, Bisping defended his title for a second time. His opponent was the Canadian Georges St. Pierre, a former UFC champ. The fight, held in New York's Madison Square Garden