Seven studies were conducted to investigate the interactions between imagery-ability and experimental treatments that parallel instructional procedures. The general orientation of the studies was to extend the concepts of imaginal and verbal coding systems to include individual differences in symbolic habits. Thus all the studies took into account…

Based on the more general principle that all thinking (including reasoning) is basically perceptual in nature, the author proposes that visual perception is not a passive recording of stimulus material but an active concern of the mind. He delineates the task of visually distinguishing changes in size, shape, and position and points out the…