The use of adjunct displays to facilitate comprehension of causal relationships in expository text

We examined whether making cause and effect relationships explicit with an adjunct display improves different facets of text comprehension compared to a text only condition. In two experiments, participants read a text and then either studied a causal diagram, studied a list, or reread the text. In both experiments, readers who studied the adjunct displays better recalled the steps in the causal sequences, answered more problem-solving transfer items correctly, and answered more questions about transitive relationships between causes and effects correctly than those who reread the text. These findings supported the causal explication hypothesis, which states that adjunct displays improve comprehension of causal relationships by explicitly representing a text's causal structure, which helps the reader better comprehend causal relationships.