Signals in Expository Prose: Effects on Reading Comprehension

Abstract

THE AUTHORS examine the effects of three signal types on relatively sophisticated readers and their comprehension of technical expository prose. A signal is generally described as a word, phrase, or statement that preannounces content and/or reveals relationships in content. Previous studies have failed to show consistent effects for signals with good comprehenders. Approximately 300 college-level subjects (pre-engineering majors) read one of four passages and then answered questions examining detail information, superordinate information, and implicit relationships. The passages were of different lengths and reading levels and covered four technical topics (nitrates, corrosion, algae, and biomedical research). Eight versions of each passage were constructed through addition, deletion, and combination of the three signal types: (a) headings, (b) previews, and (c) logical connectives. The authors conclude from the results that all three signal types can enhance comprehension, but that such facilitation depends on passage length and difficulty. In this study, the passage that was most appropriately challenging for the readers, neither too easy nor too difficult, produced the clearest effect for signals.