A cognitive developmental study of the effect of metaphor in text on the acquisition of new concepts

The purpose of this study was to investigate metaphor as an instructional device with which learners acquire new concepts from text. Metaphor was examined from a theoretical perspective that explains the function of metaphor as one of enhancing: (a) memory, by creating similarities through vivid imagery; (b) assimilation, by providing a linkage between the learner's prior knowledge and new information: (c) accommodation, by encouraging insightful understanding of new concepts.;Second, fourth and sixth grade students were screened via a battery of Piagetian tasks. On a basis of their response patterns, three different cognitive groups of twenty subjects each were formed: preoperational, concrete operational and formal operational. Two versions of instructional passages were developed to teach ten new concepts to each cognitive group. One version introduced a concept with a metaphor while the other version introduced a concept with a literal description. All passages were rated on semantic equivalence and had readabilities at least one year below the grade level for which they were written. Concept acquisition was measured by assessing the subjects' literal, interpretive and applied levels of comprehension.;The experimental method was a 2 by 3 factorial design. Data were analyzed by employing a series of Analyses of Covariance on the dependent measures: scores from recall and comprehension tasks. The independent variables were instructional treatment (metaphor or literal) and cognitive level (preoperational, concrete operational, and formal operational). In order to statistically control for the influence of prior knowledge on the effectiveness of metaphor, pretest scores of prior knowledge were used as the covariate.;Results indicated that metaphor in text was an effective instructional device for subjects at the formal stage of cognitive development. Metaphor in text was generally not effective in promoting concept acquisition for subjects who were preoperational and had a confounding effect for subjects who were concrete operational. While there was some evidence that metaphor was most effective for readers who had the least prior knowledge of the concepts being taught, this was only true for preoperational and formal level subjects. The overall results suggested that the instructional usefulness of metaphor was dependent upon the effects of cognitive development.