In order to investigate learning theories, media researchers need to explore three variables: (1) the psychological requirements of a given learning task, (2) individual differences in cognitive style, and (3) specific media characteristics. It is necessary to identify the psychological processes which underlie any specific learning task in order to study it systematically. There are also differential psychological dimensions that represent consistencies in an individual's manner of acquiring and possessing information, for example Viktor Lowenfeld's haptic and visual types. Since specific attributes are possessed by a given form of media, this three dimensional approach gives strong clues to the reasons why certain instructional methods work well with some learners while having either little or no effect on other learners. Eighteen references are cited. (Author/DS)