If you look at Facebook's efforts to understand the human brain and build digital analogs of it, one thing jumps out: the French connection.Starting with Yann LeCun, the director of Facebook's articial-intelligence research efforts since December 2013, a startling number of Facebook's AI researchers hail from France. That's no accident: French universities have some of the best AI research programs around.To date, Facebook has been housing those researchers at its headquarters in Menlo Park, Calif., or its New York office.