Primary process thinking in the same children at two developmental levels.

Analysis of primary process thinking of the same children at kindergarten level and at grade four revealed that amount of primary process thinking was relatively constant with development, contrary to predictions based on psychoanalytic theory. However, the two facets of primary process thinking, i.e., drive related ideation and formal deviations of thought follow different lines of development with the former increasing and the latter decreasing in quality and type with age.