DEKALB, Ill. — Aaric Armstead scored 21 points, went 4 for 4 at the foul line and Northern Illinois defeated Eastern Michigan 81-69 on Saturday to gain a half-step in the Mid-American Conference West Division race. Marin Maric and Levi Bradley each chipped in 14 points for Northern Illinois (14-9, 6-4), which entered the game