Cognitive and Linguistic Assessments for Dyslexia

Dyslexia is a complex learning difference that affects how the brain processes written and spoken language. Because it can look different from child to child—and often overlaps with ADHD—no single test can diagnose it. Instead, a multi-faceted assessment is needed to uncover a student’s strengths and weaknesses in several key areas of reading and language.

Phonological Awareness

Phonological awareness is the ability to hear and play with the sounds in spoken words. It includes skills such as rhyming, clapping out syllables, and blending sounds together. Many children with dyslexia struggle to connect sounds to letters, making this one of the most important areas to assess.

Signs of Weak Phonological Awareness

  • Speech errors, such as saying boo for blue or aminal for animal

  • Difficulty pronouncing longer, multisyllabic words

  • Trouble remembering which letters make certain sounds

  • Confusing similar-sounding letters or sounds (like short vowels or /b/ vs. /p/)

  • Struggling to sound out new or nonsense words

  • Relying on guessing or word shape instead of phonics when reading or spelling

  • Reading slowly or with extra effort

  • Spelling mistakes that show difficulty sequencing sounds

Phonemic Awareness

A more specific part of phonological awareness, phonemic awareness focuses on hearing and manipulating individual sounds (phonemes). For example, recognizing that “sheep” has three sounds: /sh/ /ee/ /p/. Strong phonemic awareness is the foundation for phonics instruction, spelling, and fluent reading.

Rapid Automatized Naming (RAN)

RAN tasks measure how quickly a child can name familiar items—like colors, letters, or objects. Children with dyslexia often take longer, which affects their reading speed and fluency. RAN is important because it reflects how efficiently the brain retrieves information and connects it to symbols.

Processing Speed

Processing speed refers to how quickly the brain can take in, make sense of, and respond to information. In reading, this shows up as slow word recognition, difficulty keeping up with peers, or struggling to finish timed tasks. Processing speed challenges are common in dyslexia and may also appear in ADHD.

Orthographic Coding

Orthography is the “visual memory” of written language—recognizing how letters and letter patterns look in words. Children with weak orthographic awareness often confuse letters that look alike (b/d, n/u), struggle with irregular words (like “said” or “yacht”), and may rely heavily on sounding out every word instead of recognizing it by sight.

Signs of Weak Orthographic Awareness

  • Mixing up letters or symbols that look alike (b vs. d, n vs. u)

  • Reversing or flipping letters and numbers

  • Trouble copying from the board or a book (near- or far-point copying)

  • Difficulty remembering how words are spelled or look on the page

  • Struggles with reading irregular words (like said or yacht)

  • Slow, effortful reading and weak word recognition

  • Inconsistent spelling of the same word

  • Leaving off endings when spelling (play instead of played)

  • Relying too much on sounding out words instead of recognizing them visually

  • Trouble remembering math facts or counting in sequence

  • Difficulty solving multistep math problems

Because orthographic awareness affects both reading and math, children with weaknesses here may appear to work harder and progress more slowly, even when they understand the concepts.

Morphological Awareness

Morphology is the study of meaningful word parts—like roots, prefixes, and suffixes. For example, knowing that “un-” means “not” helps students understand words like “unhappy.” This awareness supports vocabulary growth and makes reading long words easier. Children with dyslexia often need explicit teaching in morphology to strengthen decoding and comprehension.

Memory Span and Working Memory

Memory span measures how many items (like numbers or sounds) a child can hold and repeat back in order. Working memory goes further—it’s the ability to hold information while using it (for example, remembering a sequence of sounds while blending them into a word). Weak working memory makes decoding, spelling, and multi-step directions more difficult.

Basic Reading Skills and Spelling

A thorough dyslexia evaluation always includes tests of reading and spelling, since these are the core areas most affected. Standardized achievement tests are used not only to identify challenges but also to highlight strengths in areas like oral language or math.

Key Areas Assessed:

  • Word Reading & Spelling

    • Children are asked to read or spell lists of words that get progressively harder. These include both regular words (that follow phonics rules) and irregular words (that don’t). A thorough dyslexia evaluation looks at word reading and spelling accuracy as well as the size and depth of a child’s sight vocabulary. Standardized tests typically ask children to read or spell lists of unrelated words, which increase in difficulty and include both regular and irregular words.

    • Evaluators assess not just lists of words but also reading in context, since some children with dyslexia read connected text more easily than isolated words due to strong language comprehension skills.

  • Isolated Words vs. Text Reading

    • Some children with dyslexia read connected text more easily than single, isolated words, so both are evaluated.

  • Real & Nonsense Words

    • Reading both types helps measure decoding skills. Nonsense words are made-up words that follow English spelling rules but have no meaning (for example, nust or plone). They are often used in assessments to test a child’s ability to apply phonics skills, since the words can’t be recognized from memory.

  • Accuracy & Fluency

    • Evaluators check not just whether the child gets the word right, but also how quickly and smoothly they can read. Fluency depends heavily on a child’s sight vocabulary—the number of words they can instantly recognize without sounding out. In fact, the size of a child’s sight vocabulary is one of the strongest predictors of fluent reading. To assess oral reading fluency, a student reads a grade-level text aloud for one minute while the teacher follows along and notes any errors. Errors that are self-corrected do not count against accuracy, though they can affect reading fluency and rate.

      Fluency is often measured as words read correctly per minute (WRC or WCPM). To calculate this, subtract the number of errors from the total words read. For example, if a student reads 140 words and makes 5 errors, the WRC would be 135, recorded as 135/5 (words correct/errors).

      If fluency is not assessed, some children may be overlooked. For example, a child may decode words accurately but still read slowly and with great effort, which is common in dyslexia. Without fluency measures, these struggles can be misunderstood or even misdiagnosed.

      Reading accuracy is calculated by the percentage of words read correctly. Text difficulty is classified based on accuracy:

      • 99% or higher: Independent level (easy for the reader)

      • 90–98%: Instructional level (appropriate for guided practice)

      • Below 90%: Frustration level (too difficult)

      • Rule of Thumb Accuracy Quick Check:

        • Count 100 words of text.

        • Track errors by putting down a finger for each mistake.

        • If the child makes 5 or more errors before finishing, the text is too difficult.

        • Fewer than 5 errors indicates the text is likely at independent level.

By looking at accuracy, fluency, and spelling together, evaluators can build a clear picture of how a child processes written language and where targeted support is needed.

ReadIng Fluency InstructIon

The goal of fluency instruction is to build automaticity in reading, allowing students to focus their full attention on comprehension. While struggling readers may make progress in decoding accuracy and understanding, fluency often lags behind, especially for those with moderate to severe reading difficulties.

For children with the most profound dyslexia, interventions are generally more effective at improving word-reading accuracy than reading speed. Fluency, however, remains the most challenging area to remediate.

Building Fluency: Accuracy Comes First

Fluency instruction should always begin with accuracy. Early readers need strong word recognition and decoding skills before working on speed. Once accuracy is in place, the next step is helping children read sentences in a natural, “talk-like” rhythm. For younger students, fluency practice can even start with short, familiar phrases.

For children in grade 2 and above, teachers or parents should check both accuracy and reading rate before deciding where to focus instruction. A quick way to do this is by listening to the child read aloud:

  • If the child makes more than 1 error in every 10 words, instruction should target accuracy.

  • If accuracy is solid but reading is slow, then the focus should shift to building speed.

When working on rate, students should practice with texts they can already read with 95–98% accuracy, ensuring fluency grows without sacrificing understanding.

Why Multiple Assessments Matter

Each of these areas works together—like instruments in an orchestra—to make reading fluent and automatic. If one process is weak, reading can become slow and frustrating. Assessments help pinpoint where the breakdown occurs so that intervention can be tailored to the child’s needs.

Signs of Struggles in These Areas

  • Difficulty rhyming or segmenting words into sounds

  • Mispronouncing long or unfamiliar words

  • Trouble remembering letter-sound relationships

  • Slow or labored reading despite good listening comprehension

  • Reliance on guessing or context clues instead of decoding

  • Frequent spelling errors, especially with irregular words

  • Difficulty naming letters, numbers, or colors quickly

  • Forgetting instructions or struggling with multi-step tasks

Dyslexia is more than a problem with sounding out words—it involves a combination of cognitive and linguistic processes. That’s why a comprehensive assessment is essential. Understanding which skills are weak allows teachers, parents, and specialists to build an effective support plan so that children can grow into confident, capable readers.

Once I’ve evaluated your child’s strengths and challenges, I provide structured literacy tutoring tailored to their needs. Learn more about working with me as a dyslexia specialist.