Covered maze traversal models nonverbal planning, involving sequential execution of moves using learned spatial maps. To determine the neural substrate involved in maze processing, eleven adults underwent [H(2)15O]-PET while performing motor control, following the computer; visual control, choosing the wall with more dead-ends; uncovered maze, traversing fully visible mazes; covered maze, traversing mazes only locally visible. Maze processing lateralizes to the right hemisphere: uncovered maze versus controls revealed area 23 and 29 activation; covered maze versus controls activated areas 8, 10 and 19. The extrastriate region may store path information, evoked by prefrontal areas for spatial planning and navigation.