No man is an island -- unless he has a score of Twitter followers and Facebook friends but no one to go bowling with. Loneliness isn't just all in your head, but it definitely affects your brain.
The beginning stage of romance, when you're attracted to someone and can't get thoughts of him or her out of your head, is a roller coaster of emotion. But how much do you really know about the science of attraction and new love? We'll find out in this quiz.