A cognitive approach to intelligence: Attention, coding and planning.

The development of PASS Theory (Planning-Attention-Simultaneous-Successive) over the last decade is described. The theory describes behaviour as the result of the interdependent functioning of planning, attention (arousal), and coding (either simultaneous or successive) systems. The majority of the research conducted to 1979 concerned the two types of processing that take place in the coding system, simultaneous and successive coding, and relied upon principal components analyses. More recent research has examined the roles of arousal, especially in attention, and of the planning system; experimental studies and confirmatory analyses have also been conducted. The components of the theory are described, as are the operations of simultaneous and successive coding in working memory. Relationships with other theories and approaches are considered. Three areas of application and future development are examined: understanding achievement skills and learning problems, theory-based assessment of cognitive processes, and instructional design.