Can You Be Dyslexic in One Language and Not Another?

Dyslexia is a neurological condition rooted in how the brain processes written language, so it does not switch on or off depending on which language you read. But the way dyslexia shows up can differ so dramatically between languages that a person might struggle severely in English while reading passably well in Italian or Spanish. A landmark study in Science found exactly this pattern: Italian readers with dyslexia performed better on reading tasks than English and French readers with the same underlying condition, because Italian spelling is far more predictable. The condition is the same brain; the writing system changes how much trouble it causes.

Why Some Writing Systems Make Dyslexia Harder to Spot

Languages differ in how consistently their spelling maps onto their sounds. Linguists call this “orthographic depth.” A shallow or transparent orthography, like Finnish, Italian, or Spanish, has a nearly one-to-one match between letters and sounds. Once you learn the rules, you can sound out almost any word correctly. A deep or opaque orthography, like English or French, is riddled with exceptions, silent letters, and multiple ways to spell the same sound. Think of “cough,” “through,” and “dough,” three words where the same four letters produce completely different sounds.

This distinction matters for dyslexia because the core difficulty for most people with the condition involves connecting written symbols to their spoken equivalents. When the writing system makes that connection straightforward, dyslexic readers have an easier time compensating. When it does not, every irregularity becomes another stumbling block. Research on orthographic transparency and reading acquisition confirms that certain orthographies are fundamentally easier to learn than others and that these differences shape both reading strategies and how dyslexia develops in response to a given script.¹

A theoretical framework known as psycholinguistic grain size theory helps explain why. In transparent languages, children learn to read by matching small “grains” of text (individual letters) to small units of sound. In opaque languages like English, those small grains are unreliable, so children must also learn to process bigger chunks: letter clusters, whole syllables, entire words by sight. Dyslexic readers, who already struggle with sound-symbol mapping, face a double burden in opaque orthographies because they need to juggle multiple grain sizes at once.²

The Brain Signature Is Universal

If dyslexia looked entirely different from one language to the next, you might expect different brain regions to be involved. That is not what brain-imaging research shows. A synthesis of neuroimaging studies across multiple languages and writing systems found that dyslexic readers consistently show reduced activation in the same core left-hemisphere regions: the area near the back of the brain that recognizes written words, the zone where the temporal and parietal lobes meet that links print to sound, and a frontal region involved in speech production and reading effort.³ The differences between languages showed up mainly in the size and intensity of those activation patterns, not in the location. In other words, the same brain areas underperform, but the degree to which they underperform shifts depending on the demands of the writing system.

A particularly striking demonstration of this came from a study comparing Chinese-speaking and English-speaking dyslexic readers. Despite radically different scripts, different ethnic backgrounds, and testing done in different laboratories, both groups showed reduced activity in the same set of left-hemisphere brain regions compared to typical readers of their own language.⁴ The researchers described the overlap as “remarkable,” given how much the two writing systems differ on the surface.

What This Looks Like in Bilingual Children

The most direct test of whether someone can be dyslexic in one language but not another comes from studying bilingual children who read in both a transparent and an opaque script. A study of French-Spanish bilingual children with dyslexia found that their accuracy problems were mainly visible in French, the more opaque language, while speed problems showed up in both languages.⁵ So the same child might read Spanish words correctly but slowly, while reading French words both slowly and inaccurately. A teacher assessing only accuracy in Spanish could miss the dyslexia entirely.

Research on Spanish children with dyslexia who also learn English as a second language found a parallel pattern: their written performance showed similar difficulties across both languages, suggesting the underlying condition transfers rather than appearing fresh in each language.⁶ The practical upshot is that dyslexia does not vanish when you switch languages, but the symptoms that are easiest to notice do change. In a transparent language, speed is the giveaway. In an opaque language, errors pile up alongside the slowness.

How Different Scripts Demand Different Skills

The discussion so far has focused on alphabetic languages, where letters represent sounds. But what about writing systems built on entirely different principles? Chinese characters, for instance, represent meaning and syllable-level sound rather than individual consonants and vowels. Reading Chinese requires not just phonological processing but also strong visual-spatial skills, because each character is a compact arrangement of strokes and radicals that must be distinguished from thousands of similar-looking alternatives.

Research on Chinese children with dyslexia has found that the vast majority show deficits in both phonological processing and visual-spatial attention simultaneously. In one brain-imaging study, about 83% of Chinese dyslexic readers showed weaker activation in brain areas linked to both skills, suggesting these two types of difficulty tend to co-occur rather than appearing independently.⁷ A separate study confirmed that Chinese dyslexic children show deficits in verbal visual attention span alongside phonological problems.⁸ More recent work has zeroed in on a specific visual-spatial attention deficit in Chinese dyslexic children: difficulty rapidly processing orientation, a skill that matters when you need to tell apart characters that differ by the direction of a single stroke.⁹

This means a child who is dyslexic in both English and Chinese may struggle with sounds in English but with visual discrimination in Chinese, even though the root neurological condition is the same. The demands of each script pull different weaknesses to the surface.

Japanese Offers a Natural Experiment

Japanese is uniquely useful for studying this question because it uses two types of script side by side. Kana is a syllabary, where each symbol represents a spoken syllable with highly predictable pronunciation, much like a transparent alphabet. Kanji consists of characters borrowed from Chinese, where each symbol carries meaning and pronunciation is less predictable. A single reader uses both scripts every day.

A case study of a Japanese-speaking patient with acquired reading difficulties found distinct error patterns across the two scripts: semantic errors predominated when reading kanji (misreading a word as a related but different concept), while phonological errors predominated in kana (producing a word that sounded similar but was wrong).¹⁰ The researchers concluded that these were not two separate disorders but different surface expressions of the same underlying disruption to phonological processing. The script changed which errors were visible, not whether the reading difficulty existed.

Arabic Script and the Role of Visual Crowding

Arabic presents its own set of challenges. Letters change shape depending on where they sit in a word (beginning, middle, or end), many characters look very similar and differ only by the placement of dots, and the script is read right to left with a high degree of visual density. For children with dyslexia who already have trouble parsing visual detail, this creates an amplified burden.

A study comparing Arabic-English bilingual children with dyslexia found that the gap between dyslexic and typical readers was larger when reading Arabic than when reading English. The researchers attributed this to the intricate Arabic script and the effect of visual crowding, where closely packed letter shapes interfere with each other more than they do in a less dense script.¹¹ A bilingual child in this situation might score within a normal range on English reading tests while falling clearly behind in Arabic, not because they lack dyslexia in English but because Arabic’s visual demands hit them harder.

Tone Languages Add Another Layer

Mandarin and Cantonese are tonal languages, meaning the pitch contour of a syllable changes its meaning. The syllable “ma” in Mandarin can mean mother, hemp, horse, or scold depending on the tone. Research has found that Chinese children with dyslexia show weaknesses in tone awareness: the ability to hear and categorize tonal differences reliably. Over a third of dyslexic children in one study demonstrated deficits in some aspect of tone awareness, and both tone discrimination and tone production correlated with word reading ability.¹²

A related study on Cantonese-speaking children found that dyslexia correlated with difficulties in the categorical perception of tone and aspiration contrasts in speech. Critically, the researchers showed that this connection to reading was mediated by phonological awareness, confirming that dyslexia is at least partly rooted in basic speech and phonological processes regardless of whether the speech features in question are coded in the writing system.¹³ This is a finding that cuts against the idea of dyslexia being purely a visual or letter-decoding problem. Even in a language where pitch matters more than spelling rules, the same phonological processing difficulty shows up.

Why Diagnosis Gets Complicated in a Second Language

If you are a bilingual adult or a child learning to read in a second language, getting an accurate dyslexia diagnosis can be genuinely difficult. Poor reading performance in a second language might stem from limited vocabulary, unfamiliar grammar, or insufficient schooling rather than from dyslexia. A study of adult second-language learners and native speakers demonstrated that the apparent rate of dyslexia among second-language learners varied wildly depending on which reading measure was used, precisely because language proficiency and reading ability were tangled together.¹⁴

To address this problem, researchers have developed dynamic tests that measure how quickly a person learns new decoding skills rather than how well they already read. The logic is that if someone picks up a new letter-sound correspondence quickly, their poor reading is more likely due to language inexperience. If they struggle to learn even simple new correspondences, that points more reliably toward dyslexia. This approach helps separate genuine reading disability from the normal messiness of learning to read in a language you do not fully speak yet.

A study of Norwegian twelve-year-olds with dyslexia learning English as a second language found that the dyslexia group performed worse than controls across verbal and written tasks, but a closer look revealed that the subgroup with good comprehension skills barely differed from controls, while those with poor comprehension struggled enormously, especially with spelling and morphology.¹⁵ The takeaway here is that dyslexia interacts with language proficiency in complicated ways: strong comprehension can partially compensate, masking the underlying condition in a second language.

Cross-Language Transfer in Reading Interventions

One of the more encouraging findings from bilingual dyslexia research is that reading instruction in one language can improve reading in another. A study of Chinese-English bilingual children with reading difficulties found that phonics training in English benefited not just English word reading but also cross-language word reading in Chinese.¹⁶ This is a surprising result given how different the two writing systems are. The likely explanation is that strengthening the underlying phonological processing skills (sound awareness, blending, segmenting) helps across the board, even when the surface features of the scripts have almost nothing in common.

Similar cross-language transfer has been observed in other bilingual populations, with short-term improvements in English decoding appearing even when the intervention targeted the child’s first language.¹⁷ For parents and educators, this means that intervening in whichever language the child has the strongest foundation can yield benefits that spill over into their other language. You do not necessarily need separate intervention programs for each language a child reads.

Research also suggests that high exposure to English in immersive, student-centered educational settings may enhance reading even in young bilingual children with dyslexia.¹⁸ Immersion alone is not a treatment for dyslexia, but it does appear to strengthen the reading skills that underpin literacy across languages.

Italian Dyslexics Read Better Than English Dyslexics, but the Condition Is the Same

Perhaps the single most clarifying finding in this field comes from the study that compared Italian, English, and French adults with dyslexia. Italian dyslexic readers performed measurably better on reading tasks than English or French dyslexic readers, even though brain imaging suggested the same neurobiological basis. The researchers framed this as evidence for “cultural diversity and biological unity”: the biology of dyslexia is consistent across populations, but the culture’s writing system determines how severely it affects everyday reading.¹⁹

This finding reframes the question in the title. You cannot truly “have” dyslexia in one language and not another, because the underlying neural difference does not change when you pick up a different book. But you can absolutely experience dyslexia in one language and barely notice it in another. An Italian-English bilingual with dyslexia might read Italian menus and street signs comfortably while dreading English paperwork. That person is dyslexic in both languages; it is just that Italian is forgiving enough to let them get by without the struggle becoming obvious.

When the Practical Answer Matters More Than the Biological One

For people living with dyslexia across multiple languages, the biological answer (“it’s the same condition everywhere”) and the practical answer (“it’s much worse in some languages than others”) can feel like they are in tension. They are not. Both are true simultaneously, and which one matters more depends on the situation.

If you are a parent wondering whether your child’s smooth reading in Spanish but rocky reading in English means the English difficulty is “just a phase,” the biological answer matters: the child likely has dyslexia that is being masked by Spanish’s transparency. Getting assessed is worthwhile, because the difficulties in English are real and unlikely to resolve on their own. If you are an adult who grew up reading comfortably in a transparent language and then moved to an English-speaking country where reading suddenly became painful, the practical answer matters: targeted support for English reading specifically, including strategies for navigating its irregular spelling, can make a large difference even if you never needed that support before.

Clinicians working with multilingual populations increasingly recognize that testing in only one language risks both false positives (mistaking limited language proficiency for dyslexia) and false negatives (missing dyslexia because the tested language is transparent enough to mask it). The field is moving toward assessments that measure learning ability and processing speed rather than relying solely on reading accuracy in a single script, but progress is uneven across languages and countries. Many writing systems still lack validated diagnostic tools entirely.