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Knowledge For Literacy

Our guest author today is Marilyn Jager Adams, a visiting scholar in the Cognitive, Linguistic and Psychological Sciences Department of Brown University. Marilyn is internationally regarded for her research and applied work in cognition and education, including the seminal text Beginning to Read: Thinking and Learning About Print. This post is adapted from Literacy Ladders, our anthology of articles on early childhood literacy learning.

The very purpose and promise of schooling is to prepare students for responsible adult lives—to be civically minded and informed, to pursue higher education, and to find gainful work that allows them to grow and contribute to society. To accomplish this, students must be given ample support and practice in reading, interpreting, and writing about texts as complex as those that characterize life beyond high school. But here lies our great dilemma. Increasing the sophistication of assigned texts, all by itself, is unlikely to do much good. After all, we know that many students are unable to understand such rigorous texts, and nobody learns from texts that they cannot understand.

What this means is that we, as educators, need figure out how to help raise our students’ language and literacy skills to levels that enable them to understand and gain from complex texts. Working with the Albert Shanker Institute, the American Federation of Teachers, and Core Knowledge Foundation, I recently helped produce an anthology of research essays — Literacy Ladders — that addresses this challenge. Below are a couple of the key takeaways.

Comprehension Depends on Knowledge

The overarching theme of these essays is that, if we wish to advance our students’ literacy, we must devote ourselves to increasing the breadth and depth of their domain knowledge.

Through language, novel concepts are communicated in the form of novel combinations of familiar concepts. That is, new concepts and the meanings of new words can be verbally explained only in terms of known words. Sometimes a new word can be adequately explained by comparing and contrasting it with familiar concepts (e.g., a mayfly looks like a giant mosquito but it is harmless). Otherwise, we must define the word by decomposing it into familiar concepts and then piecing together the whole. Either way, the usefulness of the effort depends on the familiarity of the supporting concepts we offer.

Yet the role of prior knowledge runs far deeper. The core definition of a word is only a tiny fragment of the meaning that makes it useful in understanding language. Neuroimaging confirms that the full meaning of a familiar word extends broadly through the mind, including associations to every trace that your experience with that word or its concept has left in your memory. For instance, your full knowledge of the word “apple” extends to the traces in your memory of the many apples in your life and how they have looked, felt, tasted, smelled, or sounded (e.g., when you bit into, dropped, or sliced them); of where you were and what else and who else was there with each apple; of picking apples, peeling apples, and bobbing for apples; of cider, apple pie, caramel apples, and Waldorf salads; of apple trees, teachers’ apples, and poison apples; of “rotten apples,” “apple-cheeked,” “apple a day,” and the “Big Apple;” of Adam and Eve, William Tell, George Washington, Steve Jobs, the Beatles, and so on. The more strongly or frequently any such association has been tied to the apples in your life, the more strongly it dominates your overall concept of an apple. But all of your experiences, be they direct or linguistic, are there — waiting to be activated and used in making sense of “apple” the next time you see or hear the word.

When you encounter “apple” in conversation or text, it will automatically activate its entire, extended complex of associations in your mind, and the same thing happens when you encounter each successive word in the sentence. As the associations tied to each ensuing word in the sentence become activated, subsets of knowledge from different words that overlap effectively become "superactivated."*

Alternatively, consider what happens if — whether due to vocabulary or reading difficulties — you cannot recognize a word at all. What you lose is not just the meaning of that particular word, but also the work it was supposed to do in providing context and precise meanings for the other words around it. In between — to the extent that you recognize the word but have scant knowledge of its meaning and usage — your understanding is commensurately impoverished.

In other words, knowledge is the medium of understanding and therefore of reading with understanding.

Topical Units Can Help

Research demonstrates that, for comprehension, relevant knowledge is even more important than general reading ability. When high- and low-knowledge groups are divided into good and poor readers, those with little knowledge relevant to the text at hand perform relatively poorly, regardless of how well they read in general. In contrast — and this is important — the performance of the poor readers with higher background knowledge is generally better than that of the good readers with less background knowledge, and nearly as good as the good readers with lots of background knowledge.

Prior knowledge about a topic is like mental velcro. The relevant knowledge gives the words of the text places to stick and make sense, thereby supporting comprehension and propelling the reading process forward. In one study, scientists monitored readers’ eye movements while reading about topics that were more versus less familiar to them. Given texts about less familiar topics, people’s reading slowed down and the progress of their eye movements was marked with more pausing and rereading. In other words, not only do readers with less topic-relevant background knowledge gain less from reading about that topic, less-knowledgeable readers must also expend more time and effort to arrive at what limited understanding they do gain.**

What does information have to do with text complexity? They are closely related in two important ways. On one hand, texts that are more complex in vocabulary and syntax also tend to be more presumptuous of readers’ background knowledge. On the other, texts that strive to present more precise argument or more specific information on a topic are unavoidably more complex in vocabulary and syntax. In order for students to become comfortable and competent with these sorts of texts, they must first develop a supportive understanding of the broader topic under discussion. And that’s where topical units come in.

In a topical reading unit, all texts are about some aspect of a single main concept. Topical readings provide a natural and highly productive way of revisiting and extending learning. Across readings, as the books build interlaced networks of knowledge, the similarities, contrasts, and usages of the words gain clarity. In tandem, the stories gain plot and excitement, and the informational texts gain structure and provoke wonder. Further, as the knowledge network is enriched, the mind is ever better prepared to understand the language of each new sentence.***

The deeper domain knowledge that topical units help students acquire is of inestimable importance in itself, but topical units also bring a number of other benefits. Direct benefits include increases in reading fluency, accelerated vocabulary growth, and improvements in the spelling, style, organization, and ideas in students’ writing. Because topical units offer a means of scaffolding texts, they allow students to rapidly work their way up to engage productively with texts that would otherwise be beyond their reach. In turn, experience in understanding more sophisticated texts brings additional benefits. For example, an expert oceanographer can be expected to penetrate an advanced text in oceanography with ease. However, people who have engaged deeply with complex information in any scientific field —  experts in biogenetics, mineralogy, physics, or marine biology, for example — could be expected to be able to understand the same text far better than a person without any specialized knowledge (even if with significantly more effort than the oceanographer). The advantage of the oceanographer is due to the fact that knowledge is domain specific.****

The advantage of the other well-read scientists is due to the fact that the modes of thought and analysis that deep knowledge affords are part of the literate mind and can be applied across known and unknown domains.

Can advanced texts really be made accessible to less proficient readers in this way? Yes. As a concrete example, no text on dinosaurs would get through a readability formula for second-graders. However, having built up their vocabulary and domain knowledge in an area of interest, many second-graders are able to read and understand remarkably sophisticated texts about dinosaurs with great satisfaction. Gradually and seamlessly, students build the knowledge networks that prepare them to tackle texts of increasingly greater depth and complexity.


* For an educator-friendly review of the neural connections from letters to meaning, see: M. J. Adams, “The Relation between Alphabetic Basics, Word Recognition and Reading,” in What Research Has to Say about Reading Instruction, 4th edition, eds. S. J. Samuels and A. E. Farstrup (Newark, DE: International Reading Association, 2011), 4–24.

** For a summary of the studies in the preceding two paragraphs, see Willingham’s “How Knowledge Helps: It Speeds and Strengthens Reading Comprehension, Learning—and Thinking.” p. 42 in Literacy Ladders.

*** Be warned: Some reading programs mistake what might better be called “thematic units” for topical units. As a quick rule of thumb, if it is a topical unit, then the word or words naming the same core concept should appear frequently in every text. Note: Superficial treatments and texts about different concepts labeled with the same word don’t count.

**** E.D. Hirsch, “Beyond Comprehension: We Have yet to Adopt a Common Core Curriculum that Builds Knowledge Grade by Grade--But We Need To,” p. 54 in the Literacy Ladders.

Issues Areas


Hi Marilyn, I’ve looked at apples from all sides now, but somehow it’s apples’ allusions I recall. :-)  As always, I agree with everything you say, but I have a couple of questions. In the study of “good” and “poor” readers four-folded with more or less knowledge of the particular topics being read, what makes them generally good or poor, in spite of the reversals noted in the study? Is it just that the good readers generally have more background knowledge of the topics likely to show up in school texts and assessments, and this is a purposefully rule-proving exception? That doesn’t seem likely to be the whole story, even though it makes sense that, if a test of comprehension asks about what you know from reading a text, if you already know more about the subject, you ought to have a good chance of staying ahead in the game. My guess would be that good readers are also characterized by being able to understand (and, in the case of writing, use) the conventions through which socially developed literate communication systems represent meaning in “text” – coding it of course at the grapho-phonemic/lexical, and syntactical or grammatical level, but also at textual levels above those, including things like text structure and organization, but also in genre- and register-specific, as well as cross-cutting, forms, not to mention less linguistic things like figures, graphs, and so on. You point out that new words or concepts can only be verbally explained (“through language”) by building on known words or concepts, but then you go on to describe the role of association and direct experience, making clear that meaning is more than a Tower of – words. I understand that people who learn really different (and maybe even not so different) languages discover that the grammar and syntax of those languages are foregrounding things that they never particularly attended to. Literate communication representation systems pay attention to these things as well, but then by persisting and being reflected on, they seem to evolve and help to afford the expression of other kinds and levels of meaning. These meanings have to be decoded and encoded just as written words, and in fact speech, do, and I think kids need systematic, and I would emphasize explicit, exposure to them in the same way your suggested “topical units” do for domain knowledge. They really have to have some direct experience of the meanings being coded at these other levels or they will never really understand the code. I imagine one of the best ways for them to get such experience is for them to have to figure out how to express in writing the same or similar meanings when they have them themselves. The Common Core Standards take a stab at focusing on a few genres and talking about disciplines, but I think they provide very little guidance about how the conventions or codes involved actually might be learned. This is all very abstract. What you, and Don Hirsch, and others are suggesting about concrete curriculum seems absolutely the right way to go. I just think there’s more to be attended to (and it has very little to do with “strategies” or “skills” – though lord knows practice in using these conventions at all levels probably doesn’t hurt – and many/most kids probably do need to be helped explicitly to see what they are all about). So, good for you! Keep at it. Fritz

What a great post, Fritz, and how good to hear from you. We proposed a little bit of such stuff to the CCSS people. At the time, it was too different-from-now to make the cut. But I'm positive that you are right.

Hey Marilyn, Thank you for your insightful and reflective blog post. I could not agree more that schooling’s purpose is to prepare students for the responsibilities of adult life. Throughout our lives, we will be thwarted when miniscule to serious issues. What we choose to do when problems arise is based on the knowledge that we have gained throughout our educational experiences. Being a health teacher, I make sure to apply as many real-life scenarios and examples. Using these types of examples helps students understand the real-life application of the content that is being taught (and hopefully learned). Teacher should always strive for their students to be able to grow mentally, socially, and physically as well as contribute to society. Within the world of literature, students must be prepared to actively read, or as you call it, neuroimaging. Too many people read text, make a conclusion/inference from said text, and come to conclusions. Yet, we are missing the point of reading. As we are progressing through text, we should be able to use our “mind’s eye” and be able to paint vivid pictures to the worlds that are be comprehended. I absolutely agree that prior knowledge is vital to a student’s ability or inability to understand more complex texts. On top of challenging our students with more complex texts, educators must keep in mind the important of text relevance and application in association to the reader(s). Vocabulary takes time to build, and if the reader does not understand, more interest and knowledge will be lost rather than gained. In the coming years, I hope to apply more reading skills to help improve neuroimaging skills as well as overall comprehension, creative thinking, and real-life application. Thanks again for your blog---really got me thinking. Ken

I really enjoyed reading your take on using background knowledge as a way to prepare students to read a difficult text. I currently teach students with intellectual disabilities and have used this model without even really noticing that I was doing it. My students have significantly below standard lexile scores, and still struggle to read and comprehend texts that are on the level that has been "assigned" to them by standardized tests and other cookie cutter reading programs. I find that my students are much more successful when we discuss a topic and review the vocabulary words that are going to be addressed in that topic before addressing the text. This use of background knowledge and pre-reading should really be used by all teachers as the Common Core standards are asking us to promote text complexity and layering within our classroom curriculum. I have used reading programs before that focus on background knowledge for a few days before even looking at the text, and although I like that idea, I believe that specifically showing the students where in the text that background knowledge can be used before they read it, can be even more useful and effective. Also, your example of using background knowledge to teach 2nd graders about dinosaurs before reading a very difficult text about dinosaurs got me thinking.... if we teach and expect certain vocabularies and topics to our students- we could really instruct them on how to read anything. While lexile and reading levels are important, I think we forgot how important our instruction can be as well.

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