How ADHD and Dyslexia Overlap, and What Helps When You Have Both

Yes, ADHD and dyslexia can occur in the same person, and the overlap is often estimated at 25% to 40% in each direction. Twin studies point to shared genetic risk, and one 2025 twin study found no sign that one causes the other. Reading tutoring has been tested in children who have both.

Most of the twin and clinic studies below followed children, and most of the research describes patterns rather than proving causes. Twin studies and brain scans report patterns across groups. No study here followed adults with both conditions, so for college students we mark where the evidence runs out.

Can you have ADHD and dyslexia at the same time?

Yes. In a 2009 study in the Journal of Abnormal Child Psychology, de Jong and colleagues tested 120 children aged 8 to 12 in four groups: 24 with ADHD only, 29 with ADHD and reading disability, 41 with reading disability only and 26 typically developing controls.

It is also far from universal. In a 2025 Psychological Science twin study led by van Bergen, 77.3% of children with ADHD, dyslexia or dyscalculia had just one of them. So reading trouble does not prove ADHD, and attention trouble does not prove dyslexia. If you or your child struggle with both, ask the evaluator whether both were assessed.

How common is it to have both ADHD and dyslexia?

McGrath and Stoodley's 2019 meta-analysis in the Journal of Neurodevelopmental Disorders cites estimates of 25% to 40% bidirectional comorbidity. That figure comes from the paper's background, since the analysis itself pooled brain-imaging studies.

A general-population sample gives a closer look. Van Bergen and colleagues followed up to 19,125 twin children and 2,150 siblings from the Netherlands Twin Register at ages 7 and 10. They defined cases by a 10th-percentile cutoff on ADHD symptom scores and on reading and spelling tests, not by clinical diagnosis. In a subsample of 3,554 children, 9.2% met the ADHD cutoff and 9.8% the dyslexia cutoff. A child with ADHD was 2.7 times as likely as a child without ADHD to have dyslexia.

The authors also say clinic-based estimates are likely too high, because children with more than one condition are more likely to be referred.

Does ADHD cause dyslexia, or does dyslexia cause ADHD?

Twin studies point to shared genetic risk, and only one tested causal direction. Van Bergen's team used cross-lagged models, which test whether a trait at age 7 predicts another at age 10, and then adjusted for shared genes. They concluded the conditions co-occur because of correlated genetic risks rather than causality. They also flag a limit: a 2.5-year gap may be too long to detect causal effects, and shorter spans could still reveal them.

An older twin study points the same way. Paloyelis and colleagues, in a 2010 paper in the same journal as de Jong, analysed 1,312 twins aged 7.9 to 10.9 from the general population. The overlap between reading difficulties and ADHD inattention was driven largely by genetic factors (45%) and child-specific environment (21%). Only 11% of it came from genes shared with IQ. The link was with inattention, not hyperactivity-impulsivity, and reading difficulty was rated by parents only.

Twin studies report patterns across groups of children, so read these percentages as group figures.

What is the difference between ADHD and dyslexia?

Paloyelis and colleagues split ADHD symptoms into inattention and hyperactivity-impulsivity. Dyslexia, as Gray and Climie describe it in a 2016 review, involves difficulty decoding and spelling words. One is mainly about attention and activity, the other mainly about reading and spelling.

Some tests do not separate them cleanly. In de Jong's study, both groups were impaired in inhibition and in lexical decision (a word-or-not judgement task), and the reading-disability group was more impaired on both. Only one deficit was specific to ADHD: visuospatial working memory in children with ADHD alone. The study used a double dissociation design, which picks skills expected to be weak in one condition but not the other, and the authors found none on executive functioning or lexical decision.

The brain looks different too. McGrath and Stoodley pooled 15 dyslexia studies (417 cases, 416 controls) and 22 ADHD studies (898 cases, 763 controls). They found largely distinct gray matter differences, with no overlap at a conservative threshold and only the right caudate at a more lenient one. Scan samples are often 20 to 30 people per group, so the authors note that smaller effects may not have been reliably detected.

Do ADHD and dyslexia share symptoms like slow processing speed and working memory problems?

Partly. McGrath and Stoodley's background section lists processing speed and several executive functions, including working memory, inhibition and sustained attention, as shared risk factors across earlier studies. Van Bergen's team likewise notes that both conditions are linked to slow processing speed.

De Jong's results add a caution. Working memory for visual and spatial information was weaker only in the ADHD-only group, so not every executive skill is shared. So far, overlap shows up more in genes and thinking skills than in brain structure.

A 2023 resting-state EEG study in Brain and Behavior by Tabiee and colleagues compared 16 children with ADHD and reading disability to 16 with ADHD alone, aged 8 to 12. The combined group showed lower coherence between frontal and parietal networks. With 32 children, no control group and few girls, it is an early signal that larger studies need to confirm before anyone uses it for diagnosis.

Does ADHD medication improve reading in children who also have dyslexia?

It can ease attention symptoms, and some small studies report reading gains, but the findings are preliminary and mixed. Gray and Climie's 2016 narrative review in Frontiers in Psychology begins by saying few studies have tested ways to improve reading in children with both conditions.

On methylphenidate, they report that 59% of children with ADHD and reading disability improved on ADHD symptoms in one study. Tannock and colleagues found small effects only on colour-naming speed, with none on the alphanumeric naming speed thought to matter for word identification. Keulers and colleagues (2007) reported that children with ADHD and dyslexia read more words than untreated controls, and Bental and Tirosh (2008) reported better decoding accuracy and rapid naming, which they linked to improved attention. For atomoxetine, de Jong and colleagues found symptoms fell without a significant change in reading, while Shaywitz and colleagues reported reading gains not fully explained by lower ADHD symptoms. Gray and Climie describe the stimulant findings as preliminary support and the overall picture as conflicting.

The review calls for further study, and decisions about medication belong with a prescriber.

Does dyslexia tutoring still work if a child also has ADHD?

In two small studies, children with ADHD improved as much as those without. Verwimp and colleagues, in a 2026 paper in Dyslexia, gave 16 children with ADHD and dyslexia and 16 with dyslexia only a standard phonics programme. It ran about 40 weekly, 50-minute one-to-one sessions with psychologists. Reading fluency gains were equal in both groups, and spelling gains looked stronger in the ADHD group, who started with poorer reading and spelling. The groups were defined by diagnosis, not randomly assigned, and most children with ADHD were on methylphenidate.

Lorusso and colleagues, in a 2024 study in Frontiers in Public Health, analysed clinic records of 136 children aged 7 to 14, all of whom did a four-week web-based reading programme (Tachidino). Treated children without ADHD (82) improved more than 16 on a waiting list, and the 17 children with ADHD gained as much as the 104 without. Both studies are small and short, and neither was a randomized trial.

Forty sessions is a long stretch. A buddy on GetMotivated.ai who checks in on practice days can help you or your child keep the routine going.

What school accommodations help a student with both ADHD and dyslexia?

The studies we reviewed include no trial of accommodations for ADHD plus dyslexia, so we cannot say which work best. The nearest evidence is Pino and Mortari's 2014 systematic review in Dyslexia, which covered 15 studies of students with dyslexia in higher education. The studies were descriptive and overwhelmingly qualitative, and the authors found significant gaps. ADHD was not studied.

The review lists note-takers, dictaphones, spellcheckers and extra time as frequent adjustments. Students in the included studies reported printed handouts and advance access to slides as useful for keeping up in lectures. The review notes extra test-taking time was hardly sufficient for some students, and one student asked for oral assessment instead. The authors say research is needed to learn whether these strategies work.

So try supports one at a time and keep what helps. Our guides to ADHD in schools, 504 accommodations for ADHD and IEP accommodations for ADHD cover the K-12 route.

Do 504 accommodations continue into college?

The studies here do not answer that, and the rules and paperwork depend on your school and country. Your college's disability office is the right place to ask, and it can tell you which documents it accepts. If you have never been evaluated, ask them what evaluation they require.

Our guides to how to study with ADHD and ADHD study habits cover ways to plan around long readings.

Take ten minutes now. Find your college's disability office page, write three lines on what is hard, what you have tried and what you want to ask, and send that note with a request for their documentation requirements.