Writing and cognitive load theory

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June 24th 2019

Cognitive load theory has been described as one of the most important discussions in modern psychology that educators need to be familiar with.

Cognitive load theory has been described as one of the most important discussions in modern psychology that educators need to be familiar with. Natalie Wexler looks at what the implications of this theory are for the way we teach writing, and what it means in the classroom.

It’s been said that reading is the most difficult thing we ask students to do. In fact, that description applies more accurately to writing, which has received far less attention from both cognitive scientists and educators. Because it requires students to express themselves and not merely to receive and process information, writing imposes the greater cognitive load.

It’s clear that reading places a heavy burden on short- term or working memory – the aspect of cognition that could also be called ‘consciousness’, and which can hold only a limited number of things for a limited amount of time. When it comes to decoding, those things include the correspondences between letters and sounds; for reading comprehension, they expand to include knowledge and vocabulary relating to the topic (1). The key to successful reading is to have as many of these factors as possible stored in long-term memory – which has a virtually infinite capacity – so they don’t take up precious space in working memory and overload it.

With writing, background knowledge is even more crucial. It may be difficult to read about a subject that’s unfamiliar, but it’s virtually impossible to write about one coherently. At the same time, knowledge of the topic is only one of many factors vying for space in working memory. Even when producing a single sentence, inexperienced writers may be juggling things like letter formation, spelling, word choice, and sentence structure. When asked to write at length, they need to cope with the challenges of adhering to a topic, creating smooth transitions, avoiding repetition, and ensuring that the overall organization of the piece is coherent. All of this is in addition to absorbing the information that forms the basis for their writing, deciding what to say about it, and anticipating what a reader will need to know.

In some situations, the key to easing cognitive load is to provide what are known as ‘worked examples’. Rather than asking learners who are unfamiliar with a topic to acquire knowledge through solving problems themselves, the theory goes, teachers should have them study problems that have already been solved. In the context of math, for example, research has shown that students who study worked examples of algebra problems perform better than those who solve problems on their own, when tested later on their ability to solve similar problems. The reason appears to be that problem solving imposes such a heavy cognitive load on novice learners that they have little capacity left for transferring the strategies they’ve used into long-term memory (2).

It’s been suggested that the worked-example effect can be applied to writing as well: if teachers explicitly teach sentence structures and vocabulary, provide exemplars that illustrate these things, and lead discussions on the subject, students should be able to study the exemplars and reproduce those features in their own writing (3). But many American teachers already use a version of worked examples when trying to teach writing: they show students ‘mentor texts’ to use as models (4). Considering that a mere 25% test of American students test at the proficient level in writing (5), it’s fairly clear that that approach is not having the desired effect.

Showing students exemplar sentences rather than entire texts is definitely a step in the right direction, because it focuses students’ attention on a manageable unit. But the problem, as Greg Ashman has put it, is that there’s a difference between ‘knowing that’ and ‘knowing how’. Students may know, for example, that a sentence is ‘a set of words containing a subject and a predicate and expressing a complete thought’. Showing students examples of complete sentences and contrasting them with sentence fragments may make the concept more concrete. But many students will nevertheless fail to know how to write complete sentences and continue to use sentence fragments in their own writing. A basic problem is that the massive cognitive load that inexperienced writers face makes it difficult for them to remember to put their conceptual knowledge into practice (6).

How do we get students to know how to write well? That question is crucial, and not just because we want students to acquire writing skills. When the cognitive load is modulated, writing is perhaps the most effective way to build and deepen students’ knowledge and develop their analytical abilities. To be sure, students need some knowledge of a topic to begin writing. But once they start to write, they need to recall information they have recently learned, determine which points are important and connect them to one another, and put all of this into their own words. If students have the cognitive capacity to engage in these steps, the effect is powerful – akin to the ‘testing effect’ (the boost in retention that comes from being quizzed on recently learned material) and the similar ‘protégé effect’ (which results from explaining a topic to another person) (7,8).

When the cognitive load is modulated, writing is perhaps the most effective way to build and deepen students’ knowledge and develop their analytical abilities.

Because of the complexity of the writing process, students need more than direct instruction and worked examples to become competent writers. They need ‘deliberate practice’: repeated efforts to perform aspects of a complex task in a logical sequence, with a more experienced practitioner providing prompt and targeted feedback (9). And for many students, including many at upper grade levels, this kind of practice needs to begin at the sentence level – partly because sentences are the building blocks of all good writing, and partly because sentence-level tasks lighten the cognitive load. That’s not to say that constructing a sentence is an inherently simple task. It all depends on the content. For example, there’s nothing simple about completing this sentence: ‘Immanuel Kant believed that space and time are subjective forms of human sensibility, but _________.’

Deliberate practice in writing also needs to extend beyond English class to the rest of the curriculum. Not only does that provide teachers of history, science, math, and other subjects with a powerful tool to enhance their instruction, it also gives students more opportunities to practice the writing strategies. Eventually, many of those strategies will become lodged in long-term memory, becoming so automatic that students don’t even realize they’re using them.

When students are ready to embark on lengthier writing, where the cognitive load is even greater, they need to learn to construct clear, linear outlines that enable them to organize their thoughts, avoid repetition, and stay on track. Juggling those tasks in working memory while writing can be overwhelming even for many experienced writers. Once students have used an outline to create a draft, they can use their pre-existing knowledge of sentence-level strategies to vary their sentence structure and create smooth transitions.

While this approach to writing is still rare and unorthodox, it is gaining traction largely thanks to a US- based organization called The Writing Revolution, of which I am board chair, and a book that explains the method – also called The Writing Revolution – of which I am the co- author with Dr Judith C. Hochman. A veteran educator, Dr Hochman has developed a series of writing strategies that are designed to be taught explicitly and practiced repeatedly in a variety of contexts, with prompt feedback from a teacher. Although originally created for learning- disabled students, the method has been shown to be effective with students of all abilities, including those still learning English.

What does the method look like in practice? Let’s return to the example of students who use sentence fragments rather than complete sentences. In addition to showing students examples of fragments and complete sentences side by side, the Hochman Method has students practice distinguishing between the two – and turning the fragments into complete sentences. For older or more sophisticated students, the terms ‘subject’, ‘verb’, and ‘predicate’ might be used, but it’s sufficient to simply ask questions in functional terms. For example, if a fragment says, ‘ate a great meal,’ the teacher might ask the class, ‘Does that tell us who ate a great meal? How can we make these words into a sentence?’(10)

To derive the maximum benefit from this activity, the examples should be embedded in whatever content students are learning. A math teacher who has taught rational numbers could review – and simultaneously build writing skills – by giving students the following fragments and asking them to transform the phrases into sentences, with proper punctuation and capitalization:

  • can be expressed as a fraction or a ratio
  • rational numbers

Their responses might be:

  • A rational number is a number that can be expressed as a fraction or a ratio.
  • Rational numbers can be ordered on a number line.

Eventually, through the repeated process of identifying and correcting fragments, students will develop an understanding of how to create a complete sentence and apply that knowledge to their own writing.

Students don’t need to learn the names of grammatical structures and parts of speech for their own sake. But certain terms are useful as a shorthand for strategies that will enhance writing and lessen cognitive load. For example, the method has students learn the word ‘appositive’ – that is, a phrase that renames a noun – because it provides them with an effective strategy for varying sentence structure and expanding their responses. Once students have grasped the concept, they can be asked to provide appositives for sentences grounded in the content of the curriculum. A biology teacher might give students the sentence, ‘Natural selection, __________, results in species with favorable traits.’ A student might supply the appositive, ‘a process of evolution’.

When students have moved on to lengthier writing, they’re advised that appositives can be used to create good topic sentences – and they’ll understand what to do. Ultimately, that information will be stored in their long-term memory, along with the knowledge of other possible sentence types and structures, to be drawn on when beginning a paragraph or an essay. Rather than having their working memory occupied with searching for a way to begin – or, if they’re revising an essay, to vary their sentences – they’ll be able to devote more cognitive capacity to what they want to say.

Those of us who are already competent writers have vastly underestimated the difficulties faced by many (if not most) students in reaching that point. In years past, the assumption was that teaching rules of grammar and parts of speech was sufficient. After studies determined that approach had no positive impact on student writing, and in some cases had a negative one (11), another school of thought took hold. Its proponents assumed students would basically pick up the conventions of written language if they just read enough mentor texts and engaged in enough writing (12). Given the generally dismal results, it’s time for a new approach, supported by research: explicit instruction, mentor texts or ‘worked examples’, and the deliberate practice that will enable students to transform their conceptual knowledge into knowing how to write. Not only will schools produce better writers, but easing the cognitive load imposed by writing will lead to better thinking as well.

Natalie Wexler
Author, The Knowledge Gap: The Hidden Cause of America’s Broken Education System–and How to Fix It (forthcoming from Avery, August 2019)
Co-author with Judith C. Hochman of The Writing Revolution: A Guide to Advancing Thinking Through Writing in All Subjects and Grades (Jossey-Bass 2017)

1. Willingham, D. (2017) The reading mind: a cognitive approach to understanding how the mind reads. San Francisco, CA: Jossey-Bass, pp. 116–18.
2. Ashman, G. (2018) The truth about teaching: an evidence-informed guide for new teachers. London: SAGE Publications, pp. 42–43.
3. Needham, T. (2019) ‘Cognitive load theory in the classroom’, researchED 3, pp. 31–33.
4. Alber, R. (2014) ‘Using mentor texts to motivate and support student writers’, Edutopia [Website]. Available at: www.edut.to/2IB3ZPI.
5. The Nation’s Report Card (2011) Writing 2011. US Department of Education, Institute of Education Sciences. Washington, DC: United States Government Publishing Office. Available at: www.bit.ly/2I9LGm1.
6. Ashman, G. p. 122.
7. Roediger, H. and Karpicke, J. (2006) ‘Test-enhanced learning: taking memory tests improves long-term retention’, Psychological Science 17 (3) pp. 249–255
8. Boser, U. (2017) Learn better: mastering the skills for success in life, business and school. New York, NY: Random House.
9. Ericsson, K. A. and Pool, R. (2016) Peak: secrets from the new science of expertise. New York, NY: Houghton Mifflin.
10. This example and others are taken from Hochman, J. C. and Wexler, N. (2017) The writing revolution: a guide to advancing thinking through writing in all subjects and grades. San Francisco, CA: Jossey- Bass.
11. Graham, S. and Perin, D. (2007) Writing next: effective strategies to improve writing of adolescents in middle and high schools. Washington, DC: Alliance for Excellent Education.
12. Calkins, L. M. (1986) The art of teaching writing. Portsmouth, NH: Heinemann.