Inclusive Content Design: Addressing Cognitive and Neurodiverse Needs

Updated Aug 4, 2025 • 17 min read

Cognitive disabilities refer to conditions that affect a person's ability to think, learn, remember, or make decisions.

These disabilities can impact different mental functions, such as memory, attention, problem-solving, language understanding, and managing tasks. They might be present from birth, develop over time, or occur due to injury or illness.

What Are Cognitive Disabilities?

Cognitive disabilities refer to conditions that affect a person's ability to think, learn, remember, or make decisions. These disabilities can impact different mental functions, such as memory, attention, problem-solving, language understanding, and managing tasks. They might be present from birth, develop over time, or occur due to injury or illness.

According to a study by University College London, the number of people suffering from cognitive impairment has doubled over the past decade¹. Cognitive disabilities, as part of neurological conditions, affect a significant portion of the global population, highlighting the importance of awareness and inclusive policies.

The scale of this phenomenon is alarming, but this is partly due to advances in knowledge and better recognition of such difficulties. It is now known that more than 55 million people worldwide suffer from dementia, and about 10 million new cases are diagnosed each year².

Types of Cognitive Disabilities

Common examples include:

Intellectual Disabilities: Characterized by below-average intelligence and challenges with everyday skills like communication and social interaction.
Autism Spectrum Disorder (ASD): A developmental condition affecting social communication and behavior, making it hard for individuals to understand social cues and adapt to changes. It is important to recognize that each person with ASD has a unique experience and set of needs.
Attention-Deficit/Hyperactivity Disorder (ADHD): Marked by ongoing difficulties with managing attention, hyperactivity, and impulsivity, which affect organization and focus.
Learning Disabilities: Affect specific learning areas such as reading, writing, or math. These do not indicate low intelligence but different ways of processing information.
Traumatic Brain Injury (TBI): Results from head injuries that impair memory, problem-solving, and motor skills.
Down Syndrome: A genetic disorder caused by an extra chromosome, leading to developmental delays and intellectual disabilities.

Neurodiversity

Neurodiversity is a concept that recognizes and respects the natural variations in human brain functioning and cognitive processing. Instead of viewing neurological differences as deficits or disorders, neurodiversity emphasizes that these variations are part of the normal spectrum of human diversity.

This term often includes conditions such as:

Autism Spectrum Disorder (ASD)
Attention Deficit Hyperactivity Disorder (ADHD)
Dyslexia
Dyspraxia
Tourette Syndrome

The scale of neurodiversity

A meta-analysis published in European Psychiatry in 2024 indicates that the prevalence of ADHD among children and adolescents in Europe averages 5.0%3.

The prevalence rate can vary from country to country in Europe, for example, in France it is about 3.68% and in Spain 5-12%. A review of studies published in European Psychiatry in 2024 indicates that the prevalence of ADHD among adults in Europe averages 3.10%4.

There are numerous misconceptions surrounding neurodiversity. One of the most widespread is the belief that individuals can “grow out of” neurodivergent conditions, such as ADHD or autism. Another common misunderstanding, particularly in the context of ADHD, is the assumption that physical hyperactivity is a required symptom for diagnosis. However, recent research points to three types of ADHD:

The type with a predominance of attention deficit disorder (ADHD of the inattentive type, also called ADD)
The type with a predominance of hyperactivity and impulsivity
The mixed type- the most common

Additionally, there is a persistent stereotype that ADHD primarily affects boys, which contributes to underdiagnosis and misdiagnosis in girls and women, whose symptoms often manifest differently and may be less externally disruptive. Julia Rucklidge, in her research, points out that ADD is predominant in females by which it is often underdiagnosed due to less obvious symptoms, and favors diagnosis only in adulthood5

Global prevalence studies (through mid‑2020) estimated autism's overall rate around 0.72% for Autistic Disorder, 0.13% for Asperger Syndrome, and around 0.6%–1% for broader ASD, depending on region and diagnostic approach6. In addition, as many as 40% of people with ASD also meet diagnostic criteria for ADHD7.

The increase in the number of ADHD diagnoses in Europe may be the result of increased public awareness, reduced stigma, and better access to diagnosis, and not necessarily an actual increase in the number of cases.

COGA

The COGA (Cognitive and Learning Disabilities Accessibility Task Force) group has published a document entitled “Making Content Usable for People with Cognitive and Learning Disabilities.” Unfortunately, the document is extensive and contains only guidelines, which limits its practical application.

COGA has identified key areas that websites should pay attention to in order to make them easier to use for people with cognitive impairments and learning disabilities: clear content, assistance in understanding elements and their use, making it easier to find the information needed, support in focusing attention, and preventing errors.

Understanding the needs of people with cognitive disorders can sometimes be more difficult than, for example, in the case of visual problems, because the difficulties are often “hidden” and overlapping. Accordingly, five main symptom areas have been identified to help better understand the barriers:

Language comprehension,
Visual and visual-spatial comprehension,
Learning difficulties,
Executive function and focus,
Memory.

The classification is based on the latest research, the experience of charitable organizations and W3C and COGA guidelines. While it does not cover all possible cognitive disorders, it helps to better understand and meet the needs of these users8.

Making Content Work for Every Mind

There are numerous strategies to enhance the cognitive accessibility of content. Below are some key principles to consider during the design process.

Use Clear Content

Ensuring content is easy to read and understand is a fundamental yet often overlooked element of inclusive design. This approach is especially important for individuals with cognitive impairments, particularly those who face challenges in language processing. It is estimated that around 15% to 20% of the population experiences difficulties with reading, writing, or verbal communication.

The Cognitive Accessibility Task Force (COGA) recommends that accessible content should incorporate plain language, brief sentences and paragraphs, clear visuals, and simple video materials. While video accessibility has been previously addressed in relation to users with hearing impairments and visual content will be discussed separately, the current focus is on the organization and composition of written material. This involves careful consideration of how content is structured, the choice of vocabulary, and the most effective ways to present information to improve understanding and usability for a wider audience.

Structure

Research indicates that people generally read only about 20% to 28% of the text on a webpage. The cognitive load required to comprehend content increases with every additional 100 words. Even on pages containing just 100 words, users typically read only half of the text. Therefore, the way content is organized, particularly on longer pages, significantly affects user engagement.

The Center for Plain Language highlights that plain language involves not only simple wording but also logically arranging information for the audience. This includes designing page layouts that address users’ needs and anticipating their questions.

A clear and logical structure helps prevent readers from becoming overwhelmed and enables them to understand the context more easily. It allows users to identify where one point ends and another begins, facilitating quick access to key information without requiring them to read the entire page. This approach supports a linear, top-to-bottom page layout. The following discussion will explore how this layout is formed, from headings to paragraphs and down to individual sentences.

Paragraphs

Content beneath each heading should be organized into short sections instead of lengthy blocks of text. This approach provides natural pauses that allow readers to absorb information or take breaks as needed. Extended paragraphs, such as those spanning twenty lines, can negatively impact concentration and memory retention. Research conducted by the UK Government recommends limiting paragraphs to no more than five sentences. Additionally, paragraphs should be structured around complete ideas, avoiding splits that interrupt a thought or point midway.

Headings

Headings that clearly signal upcoming content enable users to locate information quickly and with confidence. This is particularly important not only for individuals using screen readers, who frequently navigate via headings, but also for those with attention-related challenges who may struggle to maintain focus. Clear headings provide a reference point that helps users reorient themselves when returning to the content.

Effective headings might include:

Direct questions a user may have, such as “How does two-factor authentication improve security?”
Clear, concise statements like “Benefits of Two-Factor Authentication”

Conversely, less effective headings include:

Overly long and detailed headings that reduce clarity, for example, “A Comprehensive Guide to Understanding and Implementing Two-Factor Authentication in Modern Security Systems”.
Ambiguous headings that fail to convey the section’s focus, such as “Investigating the Various Aspects of Security Measures”.
Introducing new or technical terms for the first time in a heading without explanation, unless phrased as a clarifying question.

Use an Active Voice

Sentences written in the active voice tend to be clearer. This is when the subject of the sentence performs the action, which helps readers focus on what’s happening. For example, saying, “Please submit the report by Monday”, is easier to understand than “The report should be submitted by Monday,” because the first sentence clearly identifies who needs to take action, making it more direct and engaging for the reader.

Sentences

Using short, clear, and logically structured sentences significantly enhances text readability and comprehension. It reduces the cognitive effort required to process and retain information, helping readers stay focused and avoid confusion-both in terms of content and formatting. This approach is backed by research; for example, the American Press Institute has demonstrated a direct relationship between sentence length and reading difficulty, presenting data that illustrates how shorter sentences are generally easier to understand.

Use Familiar Language

It is important to use language that your audience knows well. Avoid complicated words, technical jargon, idioms,or phrases like “pull the plug”, which can be confusing for users with cognitive disabilities, as the figurative meaning (to cancel or terminate a project) might not be immediately clear and could be taken literally. It is especially important for people with autism spectrum disorder (ASD), who often find figurative language confusing and may take such phrases literally.

Avoid Using Lots of Large Words

Research in content design shows that when readers encounter a long word with eight or nine letters, they tend to skip the shorter words that come after it. Therefore, frequently using long, complex words can make your content harder to follow, causing readers to miss important parts. This can reduce understanding and lead to users losing interest.

Provide Definitions

In certain cases, the use of acronyms or lengthy, complex terms is unavoidable, particularly when addressing specialized subjects. It is essential to provide clear explanations of these terms, either within the text itself or through easily accessible means for users. Without such clarification, readers - especially those with learning difficulties —may experience confusion and frustration, potentially leading to disengagement. Consequently, WCAG guidelines mandate accessible methods for conveying the meaning of acronyms and uncommon words (see WCAG 2.1 Success Criteria 3.1.3-4 3.1.4)

Reading Time

In addition to defining terminology, providing an estimate of the time required to read content can be highly beneficial. A "reading time" indicator offers visitors a quick approximation of how long it will take to complete the page. Although reading speeds differ among individuals, the average adult reads approximately 183 words per minute. This estimate can assist users with varying levels of language comprehension in assessing the time commitment needed. Including reading time helps set user expectations and supports individuals, particularly those with learning difficulties, in determining when and how to interact with the material.

Testing How Easy Content Is to Read

After writing content, it’s important to assess how easy it is to understand, especially when creating materials intended for a wide audience or for users with cognitive or learning difficulties. One well-established method for this is the Flesch-Kincaid readability test.

The Flesch-Kincaid system actually includes two separate tools:

1. Flesch Reading Ease Score

This test provides a score on a scale from 0 to 100. The higher the score, the easier the text is to read. For example:

Scores of 90–100 indicate very easy, conversational language- understandable by an average 11-year-old.
Scores of 60–70 are considered plain English- easily understood by 13- to 15-year-olds.
Scores below 30 suggest very complex, academic, or technical writing.

This version translates the reading ease score into a U.S. school grade level. For instance, a score of 8.0 means the text is understandable by an average 8th-grade student (around 13–14 years old). This is especially helpful when tailoring content to a specific age group or education level.

Readability testing helps ensure your content is accessible, not just in terms of layout or design, but in how easily people can engage with the language itself. This is particularly valuable for people with dyslexia, ADHD, cognitive disabilities, or for those reading in a second language.

Clear Iconography

Icons serve as an effective method to convey status or actions without relying heavily on text. Due to their widespread use across various websites, users tend to quickly recognize certain symbols. For instance, a shopping cart typically signifies a user’s cart or checkout, a bell icon is often associated with notifications, and a house icon usually represents the homepage.

Custom Icons

Uncommon or custom icons that lack clear meaning often introduce more confusion than familiar icons with slight variations. When icons are designed without adequate user testing, they are more likely to be interpreted in unintended ways. This can reduce the overall usability of a digital interface, even when the intent is to simplify the design. Familiarity with an icon from a design perspective does not guarantee that its function will be immediately apparent to users encountering it for the first time.

Sources:

1. Hallam, B., Petersen, I., Cooper, C., Avgerinou, C., & Walters, K. (2022). Time trends in incidence of reported memory concerns and cognitive decline: A cohort study in UK primary care. Clinical Epidemiology, 14, 395–408.https://doi.org/10.2147/CLEP.S350396
2. WHO. (2025). Dementia. World Health Organization https://www.who.int/news-room/fact-sheets/detail/dementia
3. Caci, H. (2023). Prevalence rate of ADHD in France: Review of the literature and results from ChiP-ARD study. Encephale, 49(6), 624–631. https://doi.org/10.1016/j.encep.2023.05.006
4. Ayano, G., Tsegay, L., Gizachew, Y., Necho, M., Yohannes, K., Demelash, S., Anbesaw, T., & Alati, R. (2024). Prevalence of ADHD in adults: An umbrella review of international studies. European Psychiatry, 67(S1), S343. https://doi.org/10.1192/j.eurpsy.2024.708
5. Rucklidge, J. J. (2010). Gender differences in attention-deficit/hyperactivity disorder. Psychiatric Clinics of North America, 33(2), 357–373. https://doi.org/10.1016/j.psc.2010.01.005
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7. Ayano, G., Tsegay, L., Gizachew, Y., Necho, M., Yohannes, K., Demelash, S., Anbesaw, T., & Alati, R. (2023). Prevalence of attention deficit hyperactivity disorder in adults: Umbrella review of evidence generated across the globe. Psychiatry Research, 328, 115449. https://doi.org/10.1016/j.psychres.2023.115449
8. Firth, A. (2023). Practical web accessibility: A comprehensive guide to digital inclusion (2nd ed., p. 185). Apress.
9. Lynch, S. (2020, sierpień 21). Cognitive disabilities: Design considerations. WebAIM. https://webaim.org/articles/cognitive/design
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