There are a number of features not directly related to the reader which may affect readability (some of these features may interact with characteristics of the reader, e.g. a picture may be motivating or demotivating). Obviously, if the print on the page is difficult to read either because it is too small or the font is an odd one, then this will contribute to reading difficulty. Clear design and layout is also important and again the reader must be taken into consideration. What may be suitable for a younger reader (comic book style, large print, etc) would be patronising for others.
Background knowledge (about content and text structure) is an important component of the reading process. The first person to use this idea in educational texts was probably Ausubel.
Ausubel suggested that "use of appropriate…..advance organizers in the teaching of meaningful verbal material would lead to more effective retention" (1960:269). His first results were not conclusive however, but Ausubel & Fitzgerald (1962) did find statistically significant results with students of "relatively poor verbal ability". Ausubel quite reasonably suggested that "[t]he pedagogic value of advance organizers obviously depends in part upon how well organized the learning material itself is."(1960:271). It seems reasonable to suggest that well written texts pitched at the right level for the intended audience might not need an advance organizer (or might need a reduced one). However, even articles written for readers who are presumably well capable of reading and understanding the text are often provided with advance organizers of one kind or another; the abstract usually provided at the beginning of an academic journal article is an example).
Advance organizers have been criticised on the grounds that they are vague (Hartley & Davies, 1976) but Ausubel claims (1978) that this is not the case and that they can only be described in general terms since the construction of an organizer "depends on the nature of the learning material, the age of the learner, and his degree of prior familiarity with the learning passage." (1978:251). This focus on individuals and individual texts seems important - we cannot apply a universal rule to all texts and all readers.
Other researchers have come to similar conclusions about the value of extra textual aids: Levin found that by using pictures and inducing readers (especially poor ones) "to attend to semantic characteristics and relationships (i.e., by having them visualize the thematic content of the passage), their reading comprehension improved dramatically." (1973:23).
Rasco et al (1975) found that the use of drawings and of "imagery instructions" (instructions to use mental imagery) facilitated learning from text.
Royer and Cable found that illustrations facilitated recall of information presented in abstract passages. They also suggest that "illustrations are likely to prove beneficial only in the situation where the text material to be learned is difficult to comprehend" (1976:206). Illustrations should have a purpose and need not be used merely to embellish easily read texts. In fact Samuels (1970) in his review of earlier literature on the use of illustrations in basal readers aimed at teaching L1 reading concluded that "pictures, when used as adjuncts to the printed text, do not facilitate comprehension". So although a picture may be worth a thousand words perhaps it depends on exactly which thousand words they are. Samuels also suggests that pictures may be useful for their effect on attitude and that pictures and text could be used separately - in separate parts of a book for example - to be referred to as needed. This idea can easily be incorporated into computer based texts. Hypertext links can call up pictures if the reader needs them. Different readers could proceed at their own pace calling up facilitative non-text aids as they wish.
The use of extra textual aids is not confined to activating content schemata and facilitating content recall. Geva (1983) used a flowcharting technique to illustrate the paragraph structure. Her technique was to represent graphically both the content and structure of the text. This is a useful technique because it both facilitates comprehension of content and sensitises the reader to the relations which hold between "idea-units and propositions" at a local and global level. As with other researchers, she found that such techniques were useful especially for less skilled readers.
Lee & Riley (1990) found that readers who had been presented with a framework which indicated rhetorical organisation of the passage found it easier to recall passage information.
McGee & Richgels (1985) also advocate teaching rhetorical structure, and the use of graphic organizers as aids to text comprehension with elementary L1 students.
Similarly, Tang (1992) found that graphic representation of knowledge structures facilitated comprehension and learning of academic texts. (see also Brown, Campione, & Day 1981; Wood & Mateja, 1983)
Signalling of text structure occurs at a textual level within the text itself as Armbruster points out:
"Types of signaling that authors use include (1) explicit statements of the structure or organization; (2) previews or introductory statements, including titles; (3) summary statements; (4) pointer words and phrases such as "an important point is….."; and (5) textual cues such as underlining, italics, and boldface." (Armbruster, 1984:204)
There seems no reason why such signalling features should not be further highlighted for weaker readers by for example the use of colour for conjunctions.
Adams (1982) found that using "script activators" facilitated vocabulary comprehension. She concluded:
"This study revealed the importance of preparing readers for what they are about to read. Teachers who create or select materials should keep in mind the backgrounds and present knowledge of their students. For example, reading selections for a beginning French class should include topics with which the students are already familiar rather than selection dealing exclusively with the target country or culture. Even though beginning students may not know all of the vocabulary in a reading selection, they are less likely to fell frustrated in their first attempts with a new language if the topic of the reading selection is already familiar to them." (Adams, 1982:158,9)
Use of extra-textual aids may facilitate comprehension but, more than that, they may also show readers how they themselves can use and create their own aids in the form of charts, diagrams etc. to help them comprehend a text. This, in the end, may be a much more valuable exercise. When readers begin to analyse a text and transfer information to another medium or format they are processing information at a much deeper level (Craik & Lockhart, 1972) and in the process learning the language. There are many ways that graphic aids may be used for learning and their usefulness are normally indicated by the text types and the information they contain, (see Johnson, 1989) but even the simple process of getting readers to underline key items helped their understanding (Fass & Schumacher, 1978). It might be noted here that students from certain cultures where texts are considered with some reverence should be encouraged to treat printed texts with less respect.
Much has been written about semantic mapping (Sinatra et al, 1986 ; Johnson et al, 1986: Clarke, 1991) normally used for activating schemata or introducing vocabulary. Clearly this is another similar idea that can be incorporated into extra-textual aids. However, like underlining mentioned above it is probably better if this is done by the readers themselves. Stahl & Vancil (1986) propose that it is not so much the mapping itself which is of use but the discussions with other readers or the teacher which accompany their drawing up which is helpful. Dean & Kulhavy (1981:63) also note that "..people who are forced to encode a spatial organizer prior to reading are more likely to retain the material studied." Merely presenting the organizer and leaving readers to use it or not is not enough.
The aids that a teacher or materials writer chooses to make available will depend not only on the readability of the text for the students he has in mind but also on the specific aspects of the textual features he wishes to highlight or reading strategies he wishes to induce. Reutzel provides a list of reasons for using these aids:
"Results show that story maps can be used to improve comprehension of both narrative and expository text. The strengths of this approach lie in the alternative it offers to traditional practices. Using a story map helps teachers and students to:
- plan and execute more purposeful, focussed reading lessons,
- organise readers' efforts toward specific comprehension objectives,
- focus questions and discussion on the important aspects of the text,
- create a workable structure for storage and retrieval of important information learned from the text,
- provide a visually coherent summary of the text,
- furnish a structure for guiding prereading experiences,
- supply students with a model for organizing and integrating text information in the content areas,
- present events and concepts in divergent visual patterns designed to emphasize specific types of relationships,
- experience a visual representation of text arrangements to encourage sensitivity to varying text patterns,
- summon the correct collection of background experiences and knowledge to facilitate comprehension of the text,
- encourage students to think about and monitor their reading." (Reutzel 1985:403)
It could be said that by providing extra-textual features we are not rendering the text itself more readable (i.e. less complex), but merely diminishing the amount of information the reader needs to decode (in a bottom-up sense) in order to make sense of it . But this is a quibble. No reader comes to a text with no background knowledge or expectations at all and the text itself activates schemata in the reader as he progresses through the text. All we are doing by providing these aids is anticipating this process so that the reader can "get stuck in" that much sooner.
From a language learning point of view the aids, in helping to make the text more comprehensible, allow the reader to draw more inferences about the language (there is more comprehensible input). From a content point of view more content can be integrated with the readers own knowledge and so more is retained.
Pictures may provide information which is not present in the text or which is not stated explicitly but must be inferred. Clearly this type of extra information would help any reader (as long as it is relevant - pictures could also provide distracting or false information). But the important point is that, as Glenburg & Langston have shown, "pictures facilitate comprehension and memory for texts, even when the pictures add no information," (1992:140).
We have assumed that texts are central and that it is the aids which are peripheral (in fact we call them adjuncts). This assumption is perhaps based on the idea that texts are the best way of getting a message across. And perhaps this is true in most cases. But there are cases where visual imagery has prime importance - advertising for example.
One problem with text is that because it is normally read in a linear fashion it constrains how mental models are built. Pictures are not constrained in such a way (there may be other constraints such as conventions of iconography). Pictures may particularly facilitate comprehension of visuo-spatial concepts but Glenberg & Langston suggest that "pictures help the comprehension and retention of text in a variety of ways" (1992:131) and that:
"….pictures assist in the construction and management of mental models in working memory. Furthermore, mental models support the noticing of relationships that are implicit in the text, thus assisting in the creation of a representation that is "richer" or more "elaborate" than would ordinarily be available from a representation of the text itself." (Glenberg & Langston, 1992:131,132)
They also suggest that pictures may ease the search for referents and that they may serve as a type of external memory (1992:149).
However they operate they seem to be powerful facilitators of comprehension..
But they should not be used just to repeat information explicitly stated in the text. If we wish to use them to facilitate comprehension maximally for the readers we have in mind they should be used also to illustrate features for which text is not the best means as in non-linear spatial organization of ideas (e.g. represents hierarchical rhetorical organisation of the text), concepts which may be deduced from the text but which are not explicitly stated, and background knowledge which the writer assumes the reader to have but which may not be the case.