From what I've seen around here, since MAP is an achievement test, it could mean the child is a good tester with a lot of crystallized knowledge, a good question guesser when faced with new difficult material, or it could support being gifted. From my own personal experience with a DS who had high scores in CogAT, MAP, WIAT, state tests, and EXPLORE at that age, his WISC V did not place him quite in the 145+ range, but the other tests did.