Cognitive sequence knowledge: what is learned?

In 4 experiments, participants performed running-arithmetic tasks. These tasks involved a sequential ordering of individual operations and a structure of subgoals that defined how calculations fit together in purpose. Consistent transitions between adjacent steps facilitated performance only when subgoal structures were relatively simple. When subgoal structures were more complex, consistent mapping of operations to serial locations produced a slight benefit. Consistency of subgoal structure produced a substantial benefit in both speed and accuracy, and some knowledge of subgoal structure integrated with knowledge of the sequence of operations. Apparently, a task's subgoal structure imposes demands that either facilitate or obscure benefits of sequence consistencies. The benefits are attributed to increased efficiency in using working memory.