An SLP explains why dyslexia affects memory, vocabulary, and word retrieval — not just reading and spelling — and what bilingual families should know.
A mom asked me a question recently that deserved a much longer answer than I could give her in a comment box. She said: everyone talks about dyslexia like it’s only about reading and writing — but I’m seeing it show up in my child’s memory, in finding the right word, in vocabulary. Am I imagining that?
She is not imagining it. And the fact that she noticed it before anyone told her to is worth saying out loud.
Dyslexia gets described in public as a reading problem, which is true but incomplete. The reading difficulty is the part you can see on a worksheet. Underneath it sits a language-processing difference, and language doesn’t stay politely inside the hour your child spends on a book. Let me walk through what dyslexia actually is, why it reaches further than decoding, and what changes — and doesn’t change — when your family is bilingual.
Most of what circulates online is the 2002 definition. The International Dyslexia Association revised it in October 2025, so if you’ve been reading older articles, you’re working from a version that’s been retired. The current definition reads:
“Dyslexia is a specific learning disability characterized by difficulties in word reading and/or spelling that involve accuracy, speed, or both and vary depending on the orthography. These difficulties occur along a continuum of severity and persist even with instruction that is effective for the individual’s peers. The causes of dyslexia are complex and involve combinations of genetic, neurobiological, and environmental influences that interact throughout development. Underlying difficulties with phonological and morphological processing are common but not universal, and early oral language weaknesses often foreshadow literacy challenges.”
A few things in there matter enormously for the question this mom asked.
It’s a continuum, not a category. “Along a continuum of severity” means there is no bright line a child crosses from not having dyslexia to having it. Two children with the same label can look very different.
It persists despite good teaching. The phrase “instruction that is effective for the individual’s peers” is the heart of it. Dyslexia isn’t what happens when a child is taught badly or hasn’t tried hard enough.
The underlying difficulty is in processing language. Phonological processing is the ability to hear, hold, and manipulate the sound structure of words. Morphological processing is handling meaningful word parts — walk / walked / walking, feliz / felicidad. Note the hedge the IDA added: these are “common but not universal.”
And the line I’d underline twice: “early oral language weaknesses often foreshadow literacy challenges.” Spoken language comes first, and it predicts what happens later with print. That sentence is why speech-language pathologists are in this conversation at all.
Here’s the answer to the actual question. If the underlying difference is in how efficiently the brain processes the sound and structure of language, then it will show up anywhere that depends on fast, precise language processing — not only when your child is looking at a page.
Verbal memory. Holding a string of sounds in mind is phonological work. When a child has to keep “go upstairs, get your shoes, and put them by the door” in their head, that’s three steps stored as language. Research on children with dyslexia consistently finds differences in verbal short-term and working memory alongside the phonological awareness differences — a review of executive functions in developmental dyslexia reports differences in verbal short-term memory and verbal working memory, and in verbal fluency tasks as well. Parents often describe this as “she forgets what I just said,” and it gets misread as not listening.
Word-finding and naming speed. There’s a well-studied task called rapid automatized naming, or RAN, where a child names a row of familiar letters, numbers, colors, or objects as fast as they can. Children and adults with dyslexia tend to be slower at it, across many different languages and writing systems (study in Portuguese-speaking children). In daily life this is the tip-of-the-tongue moment: your child knows the word, has used the word, and can’t retrieve it right now. That’s retrieval speed, not vocabulary size, and the distinction matters because the two get confused constantly.
Vocabulary — and this one is mostly downstream. This is where I want to be precise, because it’s the part most often stated sloppily. The older 2002 IDA definition named it directly, describing “reduced reading experience that can impede growth of vocabulary and background knowledge.” That’s a secondary consequence, not the core deficit. Reading is how children meet most of the words they’ll ever learn. A child who finds reading effortful reads less, meets fewer words, and accumulates less background knowledge — and the gap widens with every year, through no fault of the child’s intelligence or curiosity.
So the mom’s observation maps cleanly onto the clinical picture: memory and word-finding are close to the underlying processing difference, and vocabulary is largely a downstream effect of reading less. Those are two different mechanisms with two different implications, which is why a good plan addresses both.
One more thing worth saying, because it’s easy to lose in a list of difficulties. The Yale Center for Dyslexia & Creativity, in its signs of dyslexia material, lists strengths right next to the difficulties at every age — strong comprehension when material is read aloud, good reasoning, real curiosity. Dyslexia is an unexpected difficulty with print. It is not a ceiling on a mind.
Three things, and the research here is clearer than most parents are told.
Bilingualism does not cause dyslexia, and it does not make it worse. Raising your child in two languages did not do this, and this is not a reason to drop Spanish. I want to be blunt about that because the advice to “just pick one language” still circulates, and it costs families a heritage language for no benefit.
It shows up in both languages. Children with dyslexia generally show similar word-reading difficulties in both of their languages, which makes sense once you know the underlying difficulty is in processing language rather than in one particular vocabulary.
But it’s genuinely harder to spot in a bilingual child, because the early signs overlap with ordinary second-language learning. A child still building English can look like a child with a reading difficulty, and a child with a real reading difficulty can be waved off as “just still learning English.” This is the single biggest reason bilingual kids get identified late. Assessment that looks at both languages matters — researchers are actively working on language-independent tasks for identifying dyslexia risk in bilingual children precisely because of this problem.
Parents are often surprised that a speech therapist has anything to do with reading. We do. ASHA’s position is that speech-language pathologists play a direct role in literacy for children with communication disorders, and reading and writing fall within our scope of practice. The logic is simple: written language is built on spoken language, and phonological awareness is the hinge between them.
Now the honest limits.
Who can formally diagnose varies. Depending on your state, your school district, and the setting, a dyslexia diagnosis may come from a psychologist, an educational diagnostician, a team, or an SLP. If it matters to you, ask directly who does the identifying where you live rather than assuming.
Dyslexia is usually identified once reading instruction is underway, because the definition rests on difficulty that persists despite effective teaching — and you need teaching in place to see that. That does not mean you wait and worry. Early risk can be looked at well before a diagnosis is possible, and the oral-language groundwork that supports later reading starts in toddlerhood.
And nothing in this post is an evaluation of your child. If what you’re reading sounds like your kid, the next step is a real assessment by someone who can see and test them.
These are the sources I’d point a parent to, all free:
If you want to go deeper into how the 2025 definition was built and why it changed, the revision is written up in Annals of Dyslexia.
Dyslexia is a difficulty with word reading and spelling that sits on top of a difference in how language is processed. Because it’s a language difference and not an eyesight problem, it shows up in verbal memory and in how fast a child can pull up a word — and it quietly shapes vocabulary over the years, because a child who struggles to read reads less. Bilingualism didn’t cause it, dropping Spanish won’t fix it, and the overlap with second-language learning is exactly why these kids get caught late.
To the mom who asked: you were reading your child accurately. Bring that same list of observations to whoever evaluates them. It’s better data than any checklist.
Does Spanish TV count as exposure for a bilingual toddler? An SLP unpacks what research actually shows — when it helps, when it hurts, and how much is too much. Lindsey Carleton, MA, CCC-SLP · Aug 27, 2026
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