Depression and IQ

Posted on October 7, 2026 by Mahesh

Mind & Everyday Life

Does Depression Lower IQ? What the Studies Show

Does depression lower IQ? It lowers performance on attention, memory, speed and planning tasks while an episode lasts, and some executive and attention differences remain after recovery. A permanent loss of intelligence is not shown, and two large cohorts suggest the arrow also runs the other way.

By Arjun Vardhan, News & Research WriterPublished October 7, 2026 · 9 min readReviewed by Aarav Vardhan, Editor-in-Chief

A range chart of how far people with depression score below healthy comparison groups on cognitive tasks, in standard deviations with an IQ-style point equivalent. Executive function, memory and attention during an episode: 0.34 to 0.65 standard deviations, roughly 5 to 10 points on a scale with a standard deviation of 15 (Rock 2014). Executive function and attention in remission: 0.52 to 0.61, roughly 8 to 9 points (Rock 2014). Executive-function tests across 113 studies: 0.32 to 0.97, roughly 5 to 15 points (Snyder 2013). These are scores on specific tasks, not full-scale IQ.

Does depression lower IQ? It lowers performance on tests of attention, memory, processing speed and planning while an episode lasts, and some attention and executive-function problems can remain after mood recovers. The research does not show that depression permanently lowers a person’s underlying intelligence, and the long-term cohort data point the other way as well: a lower childhood or teenage IQ predicts a higher risk of later depression. This guide separates the questions that usually get blurred together and says what each study actually measured.

During an episode: moderate deficits on tests of attention, memory and executive function, with effect sizes of about 0.3 to 0.65 standard deviations in one meta-analysis of a single test battery. These are the kinds of tasks that overlap with parts of an IQ test.
After recovery: executive-function and attention deficits (about 0.5 to 0.6 standard deviations) were still present in people whose symptoms had remitted; memory deficits were smaller and not statistically significant.
Severity matters: across studies, more severe depression went with worse episodic memory, executive function and processing speed, but not with stored knowledge.
The other direction: in a Swedish cohort of 50,087 men and a New Zealand cohort of 1,037 people, lower earlier IQ predicted more depression later.
Not shown: a permanent loss of IQ points caused by depression. The reviews measured specific tasks, not full-scale IQ.

The topic touches several pages we already publish. The reverse claim, that high intelligence brings mood problems, is covered in high IQ and mental health and IQ and happiness. How nerves and mood distort a single sitting is covered in test anxiety and IQ scores and ADHD, autism, dyslexia and IQ test scores. This page asks the direct question about depression.

What does depression do to test performance?

The most useful evidence comes from meta-analyses, which pool many small studies. Rock and colleagues (2014) combined studies that used one computerized battery, the Cambridge Neuropsychological Test Automated Battery (CANTAB), to compare people with depression with healthy controls. They found moderate deficits in executive function, memory and attention, with effect sizes (Cohen’s d) from 0.34 to 0.65. Executive function is the set of skills for planning, switching between tasks and holding rules in mind; our guide to executive function versus IQ explains how it relates to intelligence.

Another review focused on executive-function tests. Snyder (2013) pooled 113 studies and found that major depressive disorder was reliably associated with impaired performance, with effect sizes from 0.32 to 0.97 depending on the test. People with depression also had slower processing speed, but slowed movement alone could not account for the results, and there was some evidence that the deficits were larger when current symptoms were more severe.

McDermott and Ebmeier (2009) asked a different question: does severity matter? Across the studies they pooled, more severe depression went with worse episodic memory, executive function and processing speed, but not with semantic memory (stored knowledge) or visuospatial memory. That pattern echoes what a bad night of sleep does to a score, as described in our piece on sleep loss and test performance: the speeded, attention-heavy parts take the hit and stored knowledge holds up.

What three reviews found
Review	What it combined	Main finding
Rock et al. (2014)	Studies using the CANTAB battery, people with depression versus controls, during episodes and in remission	Moderate deficits in executive function, memory and attention (d from 0.34 to 0.65); executive function and attention deficits persisted in remission (d from 0.52 to 0.61)
Snyder (2013)	113 studies of executive-function tests, major depressive disorder versus healthy controls	Reliable impairment, effect sizes 0.32 to 0.97; slower processing speed too; larger deficits with more severe current symptoms
McDermott and Ebmeier (2009)	Correlations between depression severity and test performance	Worse severity went with worse episodic memory, executive function and processing speed; no link for semantic or visuospatial memory

A Cohen’s d of 0.5 means half a standard deviation, which on an IQ-style scale with a standard deviation of 15 is 7.5 points. The ranges above therefore correspond to very roughly 5 to 10 points in the CANTAB review and 5 to 15 in the executive-function review if they were put on that scale. They are not IQ points. They are scores on specific tests, the reviews did not measure full-scale IQ, and the conversion is only there to give a sense of size.

Do the problems go away when the depression lifts?

Not entirely, on average. In the same 2014 meta-analysis, people whose depressive symptoms had remitted still showed moderate deficits in executive function and attention (d from 0.52 to 0.61). Memory deficits were smaller and not statistically significant (0.22 to 0.54). The authors concluded that cognitive impairment is a core feature of depression rather than a side effect of low mood alone.

Two cautions apply. These are comparisons of groups at one point in time, so they cannot show whether the differences were caused by depression or were already there before it began. And an average gap of half a standard deviation leaves a large overlap between the groups, so plenty of people who have recovered score within the usual range.

For IQ testing the practical point is timing. The tasks in these reviews resemble the working-memory, processing-speed and reasoning parts of a full IQ battery, so a score taken in the middle of an episode may understate what the same person scores when well. That is our inference, not something the reviews tested directly. It fits what our guides say about how a single sitting can be pulled down; see processing speed and IQ and the factors that affect an IQ test result.

Does a lower IQ raise the risk of depression?

Two long-running cohorts suggest the arrow also runs this way. Zammit and colleagues (2004) followed 50,087 Swedish men who took an IQ test at military conscription in 1969 and 1970, using hospital records over 27 years. A lower IQ was associated with a higher risk of later hospital admission for severe depression, and also for schizophrenia and other non-affective psychoses. There was no association with bipolar disorder, a contrast we unpack in bipolar disorder and IQ.

Koenen and colleagues (2009) used the Dunedin birth cohort in New Zealand: 1,037 people who took the WISC-R at ages 7, 9 and 11 and were assessed for mental disorders at ages 18, 21, 26 and 32. Lower childhood IQ was associated with a higher risk of adult depression and anxiety, with more than one disorder at a time, and with depression that persisted. The authors framed this as lower “cognitive reserve”.

Neither study shows that a low IQ causes depression. Childhood IQ can also stand in for things that raise risk on their own, such as early adversity, health problems or schooling, and the Swedish outcome was depression severe enough to need hospital admission, which tells us little about milder cases. Our overview of childhood IQ and later-life health describes the same causal puzzle for physical health. The safest reading is two-way: depression can lower performance while it lasts, and lower earlier ability is a marker of higher risk.

Does a high IQ cause depression?

The popular version of this claim leans on a 2018 survey of 3,715 American Mensa members, in which about 27% reported a mood disorder, against roughly 10% in the general population. We cover that study and its limits (self-reported diagnoses, a sample drawn from the far tail of the distribution) in high IQ and mental health. In the two population cohorts above, higher IQ went with a lower, not a higher, risk of depression, and our summary of IQ and happiness finds no strong, consistent evidence at the population level that smarter people are more likely to be depressed. One finding runs the other way, and it concerns mania rather than depression: in the Dunedin cohort, higher childhood IQ predicted a higher risk of adult mania.

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What about depression in parents and the IQ of their children?

One small study looked at this directly. Miller and colleagues (2024) followed 209 mother-child pairs from a multicenter trial and compared depression screens during pregnancy and one year after birth with the child’s WPPSI-III score at age 5. Children of mothers with a positive screen during pregnancy were more likely to have an IQ below 85 (35% versus 18%), and the same held for a positive screen after birth (47% versus 21%). But once the analysis accounted for social determinants of health and clinical characteristics, the associations were no longer statistically significant (adjusted odds ratios 1.4 and 2.1, with confidence intervals that include 1).

The sample was small and came from a trial of pregnant women with subclinical hypothyroidism, so it is a caution against over-reading the raw numbers rather than a final answer. It does fit a pattern familiar from other topics on this site, where an association shrinks sharply once family circumstances are counted: the link between waiting for a treat at age 4 and teenage achievement fell by about two thirds in our grit versus IQ guide.

Should you take an IQ test while depressed?

An IQ score is a snapshot, and its margin of error is already 2 to 3 points on a well-built test (see the margin of error explained). In the middle of a low period, poor sleep and trouble concentrating can pull the speed- and attention-heavy parts of a score down further. A sensible approach is to wait, to compare scores only when they were taken under similar conditions, and to read an unusually low result from a bad stretch as a statement about that day. The same logic applies to anyone retesting after a long gap; see can your IQ change over time.

Our IQ test gives a total score for curiosity. It cannot diagnose or rule out depression, and how much any online score can be trusted depends on the conditions it was taken in (IQ test accuracy). If low mood is lasting, a doctor or mental health professional is the right place to start. In the United States, anyone in crisis can call or text 988 to reach the Suicide & Crisis Lifeline.

For a neighboring condition with a very different pattern in the IQ data, where higher ability shows up as a risk marker in some cohorts, see bipolar disorder and IQ.

Quick answers

Does depression lower IQ permanently? The studies reviewed here do not show that. They show lower performance on specific tests of attention, memory and executive function during episodes, and some executive and attention differences that persisted in remission.
Can depression lower your score on an IQ test? It can, mostly on the speeded and attention-heavy parts, and more so when symptoms are more severe.
Do depressed people have lower IQs? On average they score lower on some cognitive tests, and in two cohorts lower earlier IQ predicted later depression. The groups overlap heavily, so a person with depression can have any IQ.
Does a high IQ cause depression? Neither population cohort found that. The claim rests mainly on a 2018 survey of Mensa members that relied on self-reported diagnoses.
How big is the effect? About 0.3 to 0.65 standard deviations for attention, memory and executive tasks in one review, roughly 5 to 10 points if put on an IQ-style scale, and larger with more severe symptoms.
Should I retest after recovering? If an earlier score came during a hard period, a retest under better conditions is reasonable; expect the usual test-to-test variation of a few points as well.

Sources

Rock, P.L. et al. (2014): Cognitive impairment in depression: a systematic review and meta-analysis, Psychological Medicine, 44(10), 2029-2040.
Snyder, H.R. (2013): Major depressive disorder is associated with broad impairments on neuropsychological measures of executive function: a meta-analysis and review, Psychological Bulletin, 139(1), 81-132.
McDermott, L.M. and Ebmeier, K.P. (2009): A meta-analysis of depression severity and cognitive function, Journal of Affective Disorders, 119(1-3), 1-8.
Zammit, S. et al. (2004): A longitudinal study of premorbid IQ score and risk of developing schizophrenia, bipolar disorder, severe depression, and other nonaffective psychoses, Archives of General Psychiatry, 61(4), 354-360.
Koenen, K.C. et al. (2009): Childhood IQ and adult mental disorders: a test of the cognitive reserve hypothesis, American Journal of Psychiatry, 166(1), 50-57.
Miller, E.S. et al. (2024): The association between perinatal depressive symptoms and child neurodevelopment, American Journal of Obstetrics & Gynecology MFM, 6(11), 101488.
Karpinski, R.I. et al. (2018): High intelligence: a risk factor for psychological and physiological overexcitabilities, Intelligence, 66, 8-23.

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Bar chart comparing self-reported anxiety and mood disorder diagnosis rates between the general population, about 10 percent each, and a 2018 survey of 3,715 members of a high IQ society, about 20 percent anxiety and 27 percent mood disorder.

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MoCA Score

Posted on October 6, 2026 by Mahesh

Scores & Scales

MoCA Score: What the Ranges Mean and How It Differs From IQ

A MoCA score is a number out of 30 from a 10-minute screen for mild cognitive impairment. See the four publisher score bands, why the 26 cut-off flags many healthy adults, what changes the score, what to do with a result and why a MoCA is not an IQ.

By Leon Falkner, Data & Research AnalystPublished October 6, 2026 · 7 min readReviewed by Aarav Vardhan, Editor-in-Chief

A score strip from 0 to 30 for the Montreal Cognitive Assessment. The publisher's ranges are severe 0 to 9, moderate 10 to 17, mild 18 to 25 and normal 26 to 30. Markers show the original cut-off of 26, the cut-off of 23 favored by a 2018 meta-analysis, and the average score of 24.7 among 2,637 cognitively unimpaired adults in the Framingham Heart Study (2026). Many healthy older adults fall below 26.

A MoCA score is a number out of 30 from the Montreal Cognitive Assessment, a 10-minute screening test for mild cognitive impairment. The publisher’s ranges are 26 to 30 normal, 18 to 25 mild, 10 to 17 moderate and 0 to 9 severe. But newer research shows that the usual cut-off of 26 flags many healthy people: in a 2026 study of 2,637 cognitively unimpaired adults, the average MoCA score was 24.7. And a MoCA score is not an IQ score. This guide explains the ranges, how the cut-off debate works, what moves the score and how it differs from an IQ test.

The ranges: 26 to 30 normal; 18 to 25 mild; 10 to 17 moderate; 0 to 9 severe, according to the publisher. Only the normal cut-off and the mild range trace to the original validation work; the publisher says the moderate and severe bands are arbitrary.
The cut-off: the 2005 validation used 26; a 2018 meta-analysis found 23 gave the best diagnostic accuracy; a 2026 study found average scores of healthy people over 60 below 23.
Education: one point is added for 12 or fewer years of formal education, up to a maximum of 30.
Not IQ: the MoCA is a screen for impairment, scored in raw points, with no validated conversion to an IQ.
What to do: a score is a prompt for a clinical evaluation, not a diagnosis.

What is the MoCA and what does it test?

Nasreddine and colleagues developed the Montreal Cognitive Assessment (MoCA) in 2005 as a 10-minute screening tool to help first-line physicians detect mild cognitive impairment (MCI), a state that often progresses to dementia. It is scored out of 30 and covers seven areas:

How the 30 MoCA points are spread across areas
Area	Points	What the points come from
Visuospatial and executive	5	a trail-making task, copying a cube and drawing a clock
Naming	3	naming three animals
Attention	6	repeating digits forward and backward, tapping to a letter, serial subtraction
Language	3	repeating two sentences and a one-minute fluency task
Abstraction	2	saying what two pairs of words have in common
Delayed recall	5	five words learned earlier, recalled without cues
Orientation	6	date, month, year, day, place and city

The fluency item is a one-minute letter F task, scored 1 point for 11 or more words; our guide to the verbal fluency test explains how those words are counted, and the digit task is related to the digit span test. We describe the sections only in general terms, not the actual items, because publishing them would weaken the test for the people who need to take it. Version 8.1 is the most recent form, and alternate versions (8.2 and 8.3) exist to reduce learning effects when the test is repeated. A MoCA-Blind version exists for people with visual impairments.

As of December 2025, the publisher says certification is optional for healthcare professionals who use the MoCA only for screening, triage or referral based on the total score, and remains required for anyone who interprets individual sections or domain-specific impairments.

What do the MoCA score ranges mean?

The publisher’s FAQ gives four bands, and it is open about where they come from: the MCI ranges were defined using Petersen criteria in the 2005 validation study, while the moderate and severe groups were arbitrarily defined by default.

The MoCA publisher’s score bands
Score	Label	Where the band comes from
26 to 30	Normal	The cut-off used in the 2005 validation study
18 to 25	Mild impairment	MCI range from the 2005 validation, using Petersen criteria
10 to 17	Moderate impairment	Arbitrary, per the publisher
0 to 9	Severe impairment	Arbitrary, per the publisher

The publisher also says a score of 18 is usually considered the line between MCI and Alzheimer’s disease, with overlap, because the diagnosis depends on the presence of cognitive and functional impairment and not on a number. That is the key limit of any band: a test score is evidence, not a verdict.

Is 26 the right cut-off?

In the 2005 validation, 94 patients with MCI, 93 with mild Alzheimer’s disease and 90 healthy older controls took both the MoCA and the Mini-Mental State Examination (MMSE). At a cut-off of 26, the MoCA detected 90% of the MCI patients and 100% of the mild Alzheimer’s patients, against 18% and 78% for the MMSE. Specificity was 87% for the MoCA and 100% for the MMSE. In other words, the MoCA caught far more impairment, at the price of flagging more healthy people. Our guide to whether an IQ test can detect dementia compares the MoCA and the MMSE in more detail.

Later work found the price was higher than first thought. Carson, Leach and Murphy (2018) pooled nine studies, chosen from 304, and found that a cut-off of 23 out of 30 gave the best diagnostic accuracy, with fewer false positives than 26. Then Muller and colleagues (2026) looked at 2,637 cognitively unimpaired adults in the Framingham Heart Study (average age 53.6, 64% college-educated). The average MoCA score was 24.7 (SD 3.0). Participants over 60 averaged below 23, and people over 70 scored below 23 regardless of education. Only college-educated people under 40 averaged near the old cut-off, at 26.3 (SD 2.4).

MoCA averages in cognitively unimpaired Framingham adults (2026)
Group	Average MoCA score	Reading
All 2,637 participants	24.7 (SD 3.0)	Close to the revised cut-off of 23
Over age 60	Below 23	Healthy group average under the revised cut-off
Over age 70	Below 23, at any education level	The cut-off flags many healthy people
Under age 40, college-educated	26.3 (SD 2.4)	Near the original cut-off of 26

The authors conclude that a cut-off of 26 produces a high rate of false positives, that 23 may also be set too high, and that clinicians and researchers need demographically appropriate, population-based norms. The practical lesson is that the same score can mean different things at 35 and at 75.

What changes a MoCA score?

Education. The standard scoring adds one point for 12 or fewer years of formal education, counted from after kindergarten, and never above 30. The Framingham norms are split by age and education, which is a reason to ask which norms a clinician is using.
Age. In the Framingham sample, averages fell below the revised cut-off after 60 even among cognitively unimpaired adults.
Repeat testing. The publisher provides alternate versions to reduce learning effects, which is why a repeat test should not reuse the same one.
Vision and physical limits. A MoCA-Blind version exists for visual impairments, and the publisher says scoring out of 25 and converting back to 30 (for example, for a person with hemiplegia) has not been validated.
Who scores it. Interpreting individual areas requires trained and certified users, per the publisher.

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How is a MoCA score different from an IQ score?

They answer different questions. An IQ score compares a person with a norm group of the same age and has a mean of 100 and a standard deviation of 15. The MoCA is a raw score out of 30 built to separate people with cognitive impairment from those without it. Healthy younger adults cluster in the upper part of the scale, so the test has little room to tell a person with a high IQ from one with an average IQ. A 30 does not mean a high IQ, and a 24 does not mean a low one. The lower averages in the Framingham study track age and education, not intelligence.

For these reasons there is, to our knowledge, no validated way to convert a MoCA score to an IQ. The IQ score converter translates between IQ scales and percentiles, and our guide to how IQ tests work explains what norming means, but neither can do anything with a MoCA total. If you want a reasoning score, take the IQ test; if you want to know whether memory or thinking has changed, the right next step is a clinician, as described next.

What should you do with a MoCA result?

Treat it as a screening result. A score below the cut-off is a reason to ask for a fuller evaluation, which usually looks at history, daily functioning and other tests, and a score above it does not rule out a problem. Because averages differ so much by age and education, ask the clinician which norms or cut-off they use. Scoring in the 18 to 25 range does not mean a person has dementia; the publisher labels it “mild impairment,” and the Framingham data show healthy adults land there often.

Quick answers

What is a normal MoCA score? The publisher says 26 to 30. In a 2026 study of 2,637 cognitively unimpaired adults the average was 24.7, and adults over 60 averaged below 23.
Is a MoCA score of 22 bad? It falls in the publisher’s mild band, but the average of healthy adults over 60 in one large study was itself below 23; it is a reason to discuss norms and follow-up, not a diagnosis.
What MoCA score indicates dementia? None by itself. The publisher says 18 is usually considered the line between MCI and Alzheimer’s disease, with overlap.
Does education change the score? Yes: one point is added for 12 or fewer years of education.
Is the MoCA an IQ test? No. It is a 30-point screen for impairment with no validated IQ conversion.
How long does it take? About 10 minutes.

Sources

Nasreddine, Z.S. et al. (2005): The Montreal Cognitive Assessment, MoCA: a brief screening tool for mild cognitive impairment, Journal of the American Geriatrics Society, 53(4), 695-699.
Carson, N., Leach, L. and Murphy, K.J. (2018): A re-examination of Montreal Cognitive Assessment (MoCA) cutoff scores, International Journal of Geriatric Psychiatry, 33(2), 379-388.
Muller, E. et al. (2026): The Montreal Cognitive Assessment at the Framingham Heart Study: a re-examination of the norms, Brain and Behavior, 16(5), e71487.
MoCA Test Inc.: frequently asked questions (score bands, education adjustment, versions and certification), accessed October 2026.

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Four comparison bars for cognitive screening tools: MoCA sensitivity 90 percent and specificity 87 percent versus MMSE sensitivity 78 percent and specificity 77 percent for detecting mild cognitive impairment.

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Verbal Fluency Test

A verbal fluency test asks you to name as many words as you can in 60 seconds, by letter (F-A-S) or category (animals). See how it is scored, why education can move the score by about 20 words, what the task really measures and what a low count can and cannot tell you.

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Verbal Fluency Test

Posted on October 6, 2026 by Mahesh

Taking a Test

Verbal Fluency Test: How It Is Scored and What Scores Mean

By Alden Cross, Intelligence Research WriterPublished October 6, 2026 · 9 min readReviewed by Aarav Vardhan, Editor-in-Chief

A bar chart of average FAS verbal fluency scores, total words in one minute for each of the letters F, A and S, among Brazilian adults aged 60 to 69 by years of schooling (Machado et al., 2009). 1 to 3 years of education: 18.3 words (14 people). 4 to 7 years: 26.1 (31 people). 8 to 11 years: 31.9 (36 people). 12 or more years: 38.7 (54 people). Education moves the score by more than 20 words.

A verbal fluency test asks you to produce as many words as you can in 60 seconds, either words that start with a letter (usually F, A and S) or items in a category such as animals. The score is the number of valid words. It is a short neuropsychological screen, not an IQ test, and what counts as a normal score depends heavily on age, education and language. This guide covers how the two forms work, how scoring rules differ, what published norms show, what the task actually measures and what a low score can and cannot tell you.

Two forms: letter (phonemic) fluency, such as F-A-S, and category (semantic) fluency, such as animals. Each is timed at one minute per letter or category.
Scoring: count valid words; repeats and words that do not fit the rule are errors. The MoCA gives its fluency item 1 point for 11 or more words beginning with F.
Norms: in a large normative study, education explained more of the F-A-S score than age (18.6% vs 11.0%), and the reverse held for animal naming (23.4% for age, 13.6% for education).
What it measures: vocabulary, speed of retrieval, working memory and executive control together, which is why researchers call it a hybrid task.
What it can tell you: low counts go with broader cognitive problems, but they do not identify which condition is responsible.

What is a verbal fluency test?

In a letter fluency test, the examiner names a letter and you say as many words as you can that begin with it before time runs out, usually 60 seconds. The classic version uses three letters, F, A and S, and adds up the totals; it is often called the FAS test, and in some versions the Controlled Oral Word Association Test (COWAT). In a category fluency test, you name members of a category, most often animals, in 60 seconds. A normative study by Tombaugh and colleagues (1999) reported norms for both and found that the total number of words across F, A and S correlated at r = .52 with the number of animals named, so the two forms overlap but are not the same skill.

The tests are quick, cheap and need no equipment, which is why they appear inside longer batteries and inside brief screens such as the MoCA. They are not core subtests of the WAIS-IV or WISC-V. For where fluency sits next to the abilities IQ tests do measure, see our guides to executive function vs IQ and processing speed and IQ.

How is a verbal fluency test scored?

The basic score is the number of correct words in the time limit. The rules for what counts differ a little between versions, so a score is only comparable to norms collected with the same rules. Two examples from published sources:

MoCA letter F item: any kind of word is allowed except proper nouns (like Bob or Boston), numbers, and words that begin with the same sound but have a different suffix, such as love, lover, loving. One point is given for 11 or more words in 60 seconds.
A Brazilian normative study of F-A-S (2009): only correct answers counted. Errors included intrusions (a valid word for the wrong letter) and perseverations (the same word said two or more times).

Researchers can also score how the words come out. In 1997, Troyer and colleagues described clustering (producing runs of related words, such as farm animals) and switching (moving to a new group), a method that a 2014 paper by Ledoux and colleagues modified to capture more about how words are organized. These extra scores are used in research and some clinics, but the raw word count is what most norms are built on.

What is a normal score on a verbal fluency test?

There is no single number. Two things move the score more than anything else: how many years of schooling the person has, and (for animal naming) how old they are. Tombaugh and colleagues tested 1,300 cognitively intact community residents aged 16 to 95, and published norms split into three age bands and three education bands. For F-A-S, education explained 18.6% of the variance and age 11.0%; for animal naming, age explained 23.4% and education 13.6%. Gender explained under 1% of either.

A 2009 study of 345 cognitively healthy Brazilian adults aged 60 to 93 shows how large the education effect can be. The average F-A-S total for the whole group was 28.3 words (SD 11.5), but it ran from about 18 words for people with 1 to 3 years of schooling to 32 to 39 for those with 12 or more years, depending on the age band.

F-A-S total words by schooling and age, Brazilian adults aged 60 and over
Years of schooling	Age 60-69	Age 70-79	Age 80+
1 to 3	18.3	18.3	20.6
4 to 7	26.1	26.0	26.2
8 to 11	31.9	28.8	28.9
12 or more	38.7	32.0	34.0

Read the table as an illustration, not as cut-offs. The sample is Brazilian, the test used Portuguese words, and some cells are small: only 5 people aged 80 or over had 12 or more years of schooling. The words and letters differ across languages, so these averages should not be applied to English. What does transfer is the lesson: a clinician comparing a score with the wrong norm group can read a normal result as a problem, or the reverse. Language background matters too: the meta-analysis summarized in our guide to bilingual advantage and IQ found a small disadvantage for bilinguals on verbal fluency specifically.

What does a verbal fluency test measure?

On the surface it measures vocabulary, but several studies show it draws on more. Shao and colleagues (2014) tested 82 older adults on letter and category fluency along with vocabulary size, lexical access speed, updating and inhibition. The number of words produced was predicted by updating ability, while the speed of the first response was predicted by vocabulary size (and, for category fluency only, lexical access speed). The authors called both tasks hybrids, which limits their value for research and clinical use. Unsworth, Spillers and Brewer (2011) reached the same kind of conclusion with latent-variable analysis, comparing fluency with working memory capacity, inhibition, vocabulary and processing speed, and describing a two-stage search in which people first look for a higher-order category and then for words inside it.

In plain terms, doing well takes a big enough vocabulary, quick retrieval, enough working memory to keep track of what you have already said, and enough control to avoid repeating or drifting off the rule. That combination is why fluency is treated as an executive-function task, and why it is more useful as a broad indicator than as a precise one. Because it leans on attention and working memory, fluency has been included among the outcomes of training studies; a four-session mindfulness study tested it alongside working memory (see our guide to meditation and IQ), though small studies like that say little about lasting change. For related timed tasks, see our guides to the digit span test and the reaction time test.

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What do low scores mean?

A low score tells you the person produced fewer words than people of the same age, education and language typically do. It does not tell you why. In a study of 33 healthy controls and 139 patients with six neurodegenerative conditions (Alzheimer’s disease, behavioral variant frontotemporal dementia, non-fluent and semantic variants of primary progressive aphasia, progressive supranuclear palsy and corticobasal syndrome), Henderson and colleagues (2023) found that total word count separated controls from every patient group. For letter fluency the area under the curve was 94.3%, and for category fluency 99.0%. But neither word count nor the properties of the words separated the patient groups from each other, and word counts tracked overall severity on a general cognitive exam.

A 2023 review of Alzheimer’s research adds that fluency tasks have been especially useful for catching early changes in semantic processing. The balanced reading is that the test is an efficient sign that something about cognition is off, not a way to say what. Education, age, language background, vocabulary and retrieval speed can all lower a count, and a meta-analysis summarized in our guide to fetal alcohol spectrum disorder and IQ put verbal fluency among the larger executive-function deficits in that condition (0.87 standard deviations below average). Children who are both gifted and struggling, covered in our guide to twice exceptional students, can be given tasks like this beyond the IQ battery. For the broader question of what IQ-style testing can and cannot say about decline, see our guide to whether an IQ test can detect dementia.

Can you try a verbal fluency test at home?

You can try the task for curiosity: set a timer for 60 seconds, pick a letter and list words. But a home count cannot be compared with published norms, because norms depend on standardized instructions, scoring rules, the language and an examiner who can judge borderline words. If you are worried about your memory or a relative’s, the useful step is a clinical evaluation, not a self-score. If what you want is a measure of reasoning, the IQ test on this site covers that, and the guide to how IQ tests work explains how scores are built.

Quick answers

What is a verbal fluency test? A timed task in which you name words that begin with a letter (F-A-S) or belong to a category (animals), usually for 60 seconds each.
How is it scored? By counting valid words; repeats and words that break the rule are errors. The MoCA gives 1 point for 11 or more F words in 60 seconds.
What is a normal score? It depends on age, education and language. In a Brazilian study the F-A-S average ran from about 18 words (1 to 3 years of schooling) to 39 (12 or more years) in ages 60 to 69.
Is it an IQ test? No. It draws on vocabulary, speed, working memory and executive control, and is not a core subtest of the Wechsler IQ batteries.
Can it diagnose dementia? No. Low counts go with broader problems but do not separate conditions from each other.
Does gender matter? In the large normative study it explained under 1% of the variance.

Sources

Tombaugh, T.N., Kozak, J. and Rees, L. (1999): Normative data stratified by age and education for two measures of verbal fluency: FAS and animal naming, Archives of Clinical Neuropsychology, 14(2), 167-177.
Machado, T.H. et al. (2009): Normative data for healthy elderly on the phonemic verbal fluency task – FAS, Dementia & Neuropsychologia, 3(1), 55-60.
Shao, Z., Janse, E., Visser, K. and Meyer, A.S. (2014): What do verbal fluency tasks measure? Predictors of verbal fluency performance in older adults, Frontiers in Psychology, 5, 772.
Unsworth, N., Spillers, G.J. and Brewer, G.A. (2011): Variation in verbal fluency: a latent variable analysis of clustering, switching, and overall performance, Quarterly Journal of Experimental Psychology, 64(3), 447-466.
Henderson, S.K. et al. (2023): Verbal fluency tests assess global cognitive status but have limited diagnostic differentiation: evidence from a large-scale examination of six neurodegenerative diseases, Brain Communications, 5(2), fcad042.
Wright, L.M., De Marco, M. and Venneri, A. (2023): Current understanding of verbal fluency in Alzheimer’s disease: evidence to date, Psychology Research and Behavior Management, 16, 1691-1705.
Troyer, A.K., Moscovitch, M. and Winocur, G. (1997): Clustering and switching as two components of verbal fluency: evidence from younger and older healthy adults, Neuropsychology, 11(1), 138-146.
Ledoux, K. et al. (2014): Capturing additional information about the organization of entries in the lexicon from verbal fluency productions, Journal of Clinical and Experimental Neuropsychology, 36(2), 205-220.
MoCA Test Inc.: frequently asked questions, and the MoCA administration and scoring instructions (letter F fluency item).

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Three finding cards about executive function and IQ from Friedman and colleagues' 2006 study of young adults. Updating, replacing what you hold in mind: highly correlated with fluid and crystallized intelligence and with WAIS IQ, a strong link. Inhibiting, holding back the automatic answer: a small, not significant relation to intelligence once the three functions were modeled together, a weak link. Shifting, switching between rules or tasks: a small, not significant relation, a weak link.

Understanding IQ

Executive Function vs IQ

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Meditation and IQ

Posted on October 6, 2026 by Mahesh

Research & Evidence

Does Meditation Increase IQ? What the Studies Actually Show

Does meditation increase IQ? The best reviews find small gains in working memory and executive function, not in IQ, and no benefit over an active comparison. See the adult and child meta-analyses, the famous two-week study, the Transcendental Meditation claims and the brain-imaging trial.

By Arjun Vardhan, News & Research WriterPublished October 6, 2026 · 8 min readReviewed by Aarav Vardhan, Editor-in-Chief

A bar chart of pooled effect sizes (Hedges g) from a 2022 meta-analysis of 45 randomized trials of mindfulness-based programs in adults. Working memory: 0.23. Executive function: 0.15. All cognitive outcomes pooled: 0.15. Against active comparison groups: no significant benefit. On an IQ scale an effect size of 1.0 would be 15 points; these are averages across cognitive tests, not IQ scores.

Does meditation increase IQ? The best reviews do not show that it does. Pooled across randomized trials in adults, mindfulness programs improve working memory and executive function by small amounts (effect sizes of about 0.15 to 0.23), no other cognitive area showed a significant benefit, and the advantage disappears when the comparison group does something active. The famous “two weeks of meditation, 16 percentile points” result came from 48 students and a reading test, not an IQ test. This guide goes through what each major study measured, what the reviews conclude and what that means for your own scores.

Adults: a 2022 meta-analysis of 45 randomized trials (2,238 people) found a pooled effect of g = 0.15 on cognition, with significant benefits only for executive function (0.15) and working memory (0.23).
The comparison matters: mindfulness programs beat inactive comparison groups but not active ones.
Children: a 2022 review of 66 trials found benefits against passive controls and no significant positive effects at follow-up.
Transcendental Meditation: a 2003 review found that the trials with large positive results recruited people favorable to TM and used passive controls.
Brain structure: an 8-week program produced no detectable change in gray matter in 218 adults in a large controlled trial.

What do the best reviews say about meditation and cognition?

Whitfield and colleagues (2022) published the first meta-analysis of objective cognitive outcomes across several domains from randomized trials of mindfulness-based programs in adults. They searched seven databases, found 56 unique studies (2,931 people) and pooled 45 of them (2,238 people). The pooled effect was small: g = 0.15 (95% CI 0.05 to 0.24). Only two areas improved significantly, executive function (0.15) and working memory (0.23). Effects were significant in non-clinical samples and in adults over 60.

Two limits matter for anyone asking about IQ. First, mindfulness programs outperformed inactive comparison groups but not active ones, such as another structured activity. Second, the authors rated most studies as having an unclear risk of bias, and statistical constraints made some p-values unreliable. The outcome is “cognitive function” sorted into domains, not an IQ score. For what those two abilities are, see our guides to executive function vs IQ and memory and IQ.

Effect sizes in the 2022 adult meta-analysis
Outcome	Pooled effect (g)	Reading
Working memory	0.23 (0.11 to 0.36)	Significant, small
Executive function	0.15 (0.02 to 0.27)	Significant, small
All cognitive outcomes pooled	0.15 (0.05 to 0.24)	Significant, small
Other cognitive domains	Not reported as significant	No clear benefit
Versus active comparison groups	Not significant	No benefit over another activity

For scale, the usual IQ scale has a standard deviation of 15 points, so an effect of 0.15 standard deviations would be roughly 2 points if it were measured on an IQ test. It was not, and a difference that size is within the usual margin of error on a single sitting. Our guide to the margin of error in an IQ score shows how large that noise is.

What did the "two weeks, 16 percentile points" study find?

Mrazek and colleagues (2013, Psychological Science) randomly assigned 48 undergraduates to a mindfulness class (26 students) or a nutrition class (22). Each met for 45 minutes four times a week for two weeks. Before and after, students took a reading-comprehension section of the GRE and an operation-span working-memory task. The mindfulness group improved on both and reported fewer task-unrelated thoughts. The paper estimates the GRE change as analogous to 16 percentile points, and improvements were mediated by less mind wandering among students who were prone to distraction at the start.

Read carefully, that is a result about attention lapses on a reading test. The sample was small, the training was short, and the outcome was a GRE section whose pre-test scores correlated at r = .45 with the students’ own SAT reading scores from college application. Nothing in it measures general intelligence. If your attention drifts during a timed test, fewer lapses can raise a score; that is a different claim from raising IQ. See our guides to test anxiety and IQ scores and to how to prepare for an IQ test.

Can four days of meditation help?

Zeidan and colleagues (2010) gave meditation-naive adults four sessions of mindfulness training or listening to a recorded book, then tested mood, verbal fluency, visual coding and working memory. Both groups improved in mood, but only the meditation group showed less fatigue and anxiety and significantly better visuo-spatial processing, working memory and executive functioning. It is a short, small study, and the later meta-analysis is the better guide to how large such effects are across many trials. The fluency task is covered in our guide to the verbal fluency test.

What about meditation for children?

Dunning and colleagues (2022) updated their meta-analysis of randomized trials of mindfulness programs for people under 19: 66 trials with 20,138 participants. Compared with passive controls, the programs improved anxiety and stress, attention, executive functioning and behavior, with effect sizes from 0.12 to 0.35. Compared with active controls, they were better only for anxiety and stress (0.11) and mindfulness itself (0.24). In studies with a follow-up, there were no significant positive effects. The authors conclude that enthusiasm for these programs has arguably run ahead of the evidence, and that the evidence is of low quality and inconclusive. Our guides to whether you can improve your IQ and to growth mindset and intelligence cover what the evidence says about changing scores.

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Does Transcendental Meditation raise IQ?

The strongest-sounding claims come from Transcendental Meditation (TM). A 1991 study in Personality and Individual Differences followed 100 college students for two years: 45 at a university whose curriculum includes twice-daily TM practice and 55 at another university. The TM-university group improved significantly on Cattell’s Culture Fair Intelligence Test, and the paper presented the results as improved performance on intelligence-related measures. Several of its authors were affiliated with the TM university, and students were not randomly assigned to the two schools.

Canter and Ernst (2003) later reviewed the randomized evidence. Of 107 articles on TM and cognitive function they found, only 10 met its criteria (randomized, with objective measures of cumulative effects). Four reported large positive effects, four were completely negative and two were largely negative. All four positive trials recruited people favorably predisposed toward TM and used passive control procedures; the other six recruited people with no special interest and mostly used structured controls. The review concluded that the claim of a specific, cumulative effect on cognitive function was not supported, and read the positive trials as an expectation effect. For another popular route to a sharper mind, see our guide to whether brain-training apps work.

Does meditation change the brain?

A common step in the argument is that meditation visibly grows the brain, and so must raise intelligence. Kral and colleagues (2022) tested the structural claim in two combined randomized trials of meditation-naive adults (n = 218): 75 were assigned to an 8-week mindfulness-based stress reduction program, 73 to an active control and 70 to a waitlist. They found no change in gray matter volume, gray matter density or cortical thickness compared with either control group, either across the whole brain or in regions taken from earlier studies. Brain imaging results from small, uncontrolled studies should be read with that in mind.

How should you read a headline about meditation and IQ?

A review of the field by Van Dam and colleagues (2018) warned that misinformation and poor methodology around mindfulness may leave people misled and disappointed, and set out an agenda for stronger research, including attention to possible adverse effects. Four questions help with any headline:

Was there an active comparison group? A waitlist can only show that doing something beats doing nothing.
How many people, and who ran it? 48 students is a small trial; studies run by people who teach or sell the method deserve extra scrutiny.
Was the outcome an IQ test? Reading, attention and working-memory tasks are not the same as a full-scale score.
Was there a follow-up? Effects that fade after the program ends are not lasting changes.

None of this means meditation is pointless. Reductions in stress and anxiety, and small gains in attention and working memory, are reasonable benefits to want. It means the honest answer to the IQ question is that the evidence does not show a rise, and that you should use the IQ test for what it is: a snapshot of reasoning, not a tracker for a habit. If test-day performance is the goal, our guides to sleep and IQ and sleep loss and test performance cover another factor.

Quick answers

Does meditation increase IQ? Not according to the best reviews. They find small gains in working memory and executive function, not in IQ.
How big is the benefit? A pooled g of 0.15 on cognition in adults, and 0.23 for working memory.
Does mindfulness beat other activities? In adults, programs beat inactive comparison groups but not active ones.
Does Transcendental Meditation raise intelligence? A 2003 review of randomized trials found no support for a specific effect; the positive trials used passive controls and favorable recruits.
Does meditation grow the brain? An 8-week program showed no structural change in 218 adults.
Is it worth doing anyway? For stress, anxiety and attention, perhaps; for IQ, there is no evidence.

Sources

Whitfield, T. et al. (2022): The effect of mindfulness-based programs on cognitive function in adults: a systematic review and meta-analysis, Neuropsychology Review, 32(3), 677-702.
Mrazek, M.D. et al. (2013): Mindfulness training improves working memory capacity and GRE performance while reducing mind wandering, Psychological Science, 24(5), 776-781.
Zeidan, F. et al. (2010): Mindfulness meditation improves cognition: evidence of brief mental training, Consciousness and Cognition, 19(2), 597-605.
Dunning, D. et al. (2022): Do mindfulness-based programmes improve the cognitive skills, behaviour and mental health of children and adolescents? An updated meta-analysis of randomised controlled trials, Evidence-Based Mental Health, 25(3), 135-142.
Canter, P.H. and Ernst, E. (2003): The cumulative effects of Transcendental Meditation on cognitive function: a systematic review of randomised controlled trials, Wiener Klinische Wochenschrift, 115(21-22), 758-766.
Cranson, R.W. et al. (1991): Transcendental Meditation and improved performance on intelligence-related measures: a longitudinal study, Personality and Individual Differences, 12(10), 1105-1116.
Kral, T.R.A. et al. (2022): Absence of structural brain changes from mindfulness-based stress reduction: two combined randomized controlled trials, Science Advances, 8(20), eabk3316.
Van Dam, N.T. et al. (2018): Mind the hype: a critical evaluation and prescriptive agenda for research on mindfulness and meditation, Perspectives on Psychological Science, 13(1), 36-61.

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Two-panel bar chart comparing memory athletes and matched controls: 71 versus 40 words recalled after 20 minutes, but nearly identical fluid-reasoning scores of 128.1 versus 128.4

Understanding IQ

Memory and IQ

The world’s best memory athletes can memorize 71 shuffled words in twenty minutes. Their IQ scores are not measurably different from a matched control group who could only manage 40. If a spectacular memory is not the same thing as a high IQ, what actually is the difference?

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Research & Evidence

Sleep and IQ

This site’s news desk has already covered what one bad night does to a test score on the day it is taken. This is a different and, for children especially, more consequential question: what years of too little sleep do to the cognitive systems an IQ test measures in the first place.

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Verbal Fluency Test

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Twice Exceptional (2e)

Posted on October 6, 2026 by Mahesh

Understanding IQ

Twice Exceptional (2e): What It Means and How Students Are Identified

Twice exceptional (2e) means gifted and disabled at the same time, such as high reasoning with dyslexia, ADHD or autism. See the research definition, how one IQ score can hide the pattern, how students are identified and what 2026 data show about how many are found.

By Alden Cross, Intelligence Research WriterPublished October 6, 2026 · 10 min readReviewed by Aarav Vardhan, Editor-in-Chief

A range chart of how many students are identified as both gifted and disabled. Students with a disability in all US public schools: 15 percent (National Center for Education Statistics, 2024). Students identified as both gifted and in special education or a Section 504 plan, across 23 states that reported: from 0 percent to 18.66 percent, with all but two states below 10 percent (NAGC state of the states, 2022-23). The gap suggests twice-exceptional students are underidentified.

Twice exceptional (2e) means a student is gifted and has a disability at the same time, such as strong reasoning ability together with dyslexia, ADHD or autism. The standard research definition, published by Reis, Baum and Burke in 2014, describes students with the potential for high achievement or creative productivity in one or more areas who also have one or more disabilities under federal or state criteria. This guide explains what that means in practice, why a single IQ score can hide the pattern, how students are identified, and what the newest data say about how many are actually found.

What it is: an educational label for the combination of high potential and a disability, not a separate diagnosis. Two-sided by definition, and very varied from child to child.
Why it is missed: each side can hide the other. Disabilities can limit how visible the strengths are, and strengths can compensate for the disability in the early grades.
The IQ angle: a single full-scale score blends strengths and weaknesses; index scores show the spread.
How many: no settled figure. US states that reported identified from 0% to 18.66% of students as both gifted and in special education, with all but two under 10% (NAGC, 2026).
What helps: strengths-based, talent-focused support alongside accommodations, with gifted and special education staff working together.

The pairing sits between topics our readers already ask about. Our guides to the signs of a gifted child, high IQ and ADHD, autism and IQ and dyslexia and IQ each cover one half. This page covers the combination itself.

What does twice exceptional mean?

The 2014 definition by Reis, Baum and Burke, published in Gifted Child Quarterly, offered an operational definition, and the National Association for Gifted Children (NAGC) uses it in its August 2026 position statement on identifying and serving twice-exceptional students. Two parts matter. The strength side is potential for high achievement or creative productivity in a domain such as math, science, the arts or another area of human productivity, which is wider than an IQ cut-off. The disability side is whatever federal or state eligibility criteria recognize, for example a specific learning disability, ADHD or autism.

NAGC stresses how varied the group is. Twice-exceptional students differ cognitively and emotionally, and their schooling can look uneven: inconsistent grades or test scores, frustration, insecurity or low motivation, and social or emotional skills that lag behind their reasoning. That unevenness is the signature, and it is also why a quick look at report-card grades or one score so often misses them. For how a gifted range is usually drawn on IQ scales, see our guide to gifted cut-off scores.

Which conditions can go with giftedness?

Any disability recognized under federal or state criteria can, in principle, pair with high ability. Common pairings in the research literature are specific learning disabilities such as dyslexia and dysgraphia, ADHD and autism. The studies below are small and specific, and each used a different design, so they illustrate the range of profiles rather than giving one typical 2e child.

Three studies of giftedness paired with a disability
Pairing	Study	What it found
Gifted and autism	Assouline et al. (2012), 59 students with ability of 120 or above and an autism diagnosis	WISC-IV working memory and processing speed indexes were positively related to achievement in math, reading and written language. The autism diagnosis and Verbal Comprehension were not related to achievement.
Gifted and dyslexia	Alonso Benito et al. (2026), Spanish secondary students	Gifted students with dyslexia showed an uneven reading and writing profile: weaker lexical and syntactic processing, relatively stronger semantic skills. On some measures they scored above the dyslexia-only group and below the gifted-only group.
Gifted and ADHD	See our guide	Covered in high IQ and ADHD and ADHD and IQ; NAGC also cites a 2024 study of career outcomes for academically advanced students with ADHD, which varied.

Why can one IQ score hide it?

A composite score averages. When a student’s strengths and weaknesses sit on different indexes, the full-scale number can land in a middle band that describes neither. The WISC-V illustrates the idea: its Full Scale IQ is built from seven subtests, while the optional General Ability Index uses five subtests (Similarities, Vocabulary, Block Design, Matrix Reasoning and Figure Weights) and leaves out working memory and speed. Our guides to WISC-V index scores and to full-scale IQ vs index scores show how the pieces fit together, and how to read an IQ test report explains the layout.

The autism study above shows why the pieces matter. Among 59 high-ability students, the working-memory and processing-speed indexes tracked achievement, while Verbal Comprehension did not. A reader who looked only at a strong verbal score would miss the part of the profile that was doing the predicting. NAGC makes the same point in plain terms: when identification relies on a composite instead of domain-specific scores, a disability can limit how much of the strength shows. See also processing speed and IQ and executive function vs IQ.

How do strengths and weaknesses mask each other?

NAGC describes two directions. A student’s disability may limit how far the strengths are visible. Or the strengths may compensate for the disability, especially in early grades, so nothing looks wrong enough to trigger an evaluation. The second route has a legal edge in the United States. To qualify for an Individualized Education Program or a Section 504 plan, a student must have a disability and need specially designed instruction or accommodations, and in practice that second step often depends on below-average grades or scores. Many twice-exceptional students do not show them, particularly under tiered support systems that screen on low achievement.

The result, in NAGC’s words, is that supports may arrive only when the demands finally outpace what the student can compensate for. The same logic explains why federal rules for specific learning disabilities do not require a severe gap between ability and achievement, a point covered in our guide to dyslexia and IQ. Even so, researchers still disagree on how to define unexpected underachievement. A 2006 review by Lovett and Lewandowski argued that uncritical acceptance of the idea of giftedness combined with a learning disability had led to unsound identification procedures, and that many suggested practices were unsupported or contradicted by research. A 2026 expert-panel (Delphi) study of specific learning disability found agreement on the importance of academic deficits and exclusionary criteria, but persistent disagreement about discrepancy methods and about what they mean for identifying twice-exceptional learners.

How many students are twice exceptional?

There is no settled number, and the available figures measure different things. In the United States, NAGC reports that representatives from 23 states gave the share of students identified as both gifted and in special education or a Section 504 plan, and the figures ranged from 0% to 18.66%, with all but two states below 10%. For comparison, the National Center for Education Statistics (2024) estimates that 15% of all public school students have a disability. NAGC reads that gap as a sign that twice-exceptional students are probably underrepresented in gifted programs.

Three figures that are not the same thing
Figure	Source	What it counts
0% to 18.66%	NAGC, citing the 2022-23 State of the States (23 reporting states)	Students already identified as both gifted and in special education or a 504 plan
15%	National Center for Education Statistics, 2024	All public school students with a disability
About 5.9%	Almulhim et al. (2026), 6,875 students in Saudi Arabia	A screening estimate of possible twice exceptionality; the authors call it exploratory

The Saudi study is a useful reminder of how estimates are built. Students in grades 2 to 12 were first flagged for a possible learning disability when their achievement in two subjects differed by more than 1.5 standard deviations. That flagged 23.6% of them. A giftedness test then suggested that 24.5% of the flagged students might be gifted, which gave roughly 5.9% of the whole sample. The authors say broader replication is needed before policy conclusions. Treat it as one country’s screening estimate, not a US rate.

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Where would your own score land?

Find your IQ score now! →

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Who gets missed?

NAGC points to a double bind. Students from minoritized groups are underserved by talent-development programs and overrepresented in special education, and students in special education are less likely to be referred for advanced learning. A twice-exceptional student from such a group faces both barriers.

One well-studied lever is universal screening. In a large urban district that began screening every second grader for gifted programs, Card and Giuliano (2016) found that, with no change in eligibility standards, the share of economically disadvantaged and minority students placed in gifted programs rose substantially. Black and Hispanic students, students receiving subsidized school lunches, English language learners and girls had all been underreferred when the district relied on parents and teachers. Our guide to universal screening for gifted programs covers the mechanics.

How is a twice-exceptional student identified?

NAGC says comprehensive assessment is the best way to understand the full range of a twice-exceptional student’s abilities, and it also says this is rarely feasible in gifted-identification systems because of limited funding. Its recommendations for schools are practical:

Offer universal screening or eligibility assessment to all students rather than relying on referrals.
Look at domain-specific strengths, such as math or language scores, not only a composite ability score.
Use a broader view of educational impairment for disability supports, one that is not limited to below-average grades.
Put special education and gifted specialists in the same conversation, with school psychologists and counselors involved.
Train educators to use data to identify and serve these students.

For parents, the practical translation is to ask the school for a comprehensive evaluation that looks at both strengths and difficulties, and to ask for index-level scores rather than only a total. Our guide to IQ testing for children explains what the evaluations measure, and the WPPSI-IV and Woodcock-Johnson guides cover two tests that are often used. Evaluators can also add tasks beyond the IQ battery, such as timed word-generation tasks; our guide to the verbal fluency test describes one.

What helps a twice-exceptional student?

Few researchers have tested educational interventions for this group, partly because the profiles differ so much. The recommendations NAGC reports coalesce around a strengths-based, talent-development approach: psychological well-being, acceptance of difference, enough time for academic work and positive relationships, with accommodations for the area of difficulty and opportunities to excel in the talent area. A 2024 case study described three supports: a culture of acceptance, professional development on high-ability students and a learning specialist who understands twice exceptionality. NAGC also notes that families often carry the cost of the extra educational and psychological resources.

An online score cannot substitute for any of this. The IQ test on this site gives a total and is useful for curiosity, but it is not an evaluation, and it cannot identify a disability.

Quick answers

What does twice exceptional (2e) mean? Gifted, or with high potential in a domain, and also having a disability under federal or state criteria.
Is 2e a diagnosis? No. It is an educational label for the combination; the disability side is determined separately.
Can a 2e student have an average IQ score? A composite can land in a middle band when strengths and weaknesses average out, which is why index scores and domain scores matter.
How common is it? Unknown. US states that reported identified between 0% and 18.66% as both gifted and in special education or a 504 plan; one 2026 Saudi screening estimate was about 5.9%.
Which program should a 2e student be in? NAGC recommends access to talent development and to accommodations, with both sets of specialists involved.
Do 2e students need to be failing to get support? They often do not, which is the problem: eligibility for disability supports can depend on below-average performance.

Sources

National Association for Gifted Children (August 2026): Identifying and Serving Gifted Children Who Are Twice Exceptional (position statement).
Reis, S.M., Baum, S.M. and Burke, E. (2014): An operational definition of twice-exceptional learners: implications and applications, Gifted Child Quarterly, 58(3), 217-230.
Card, D. and Giuliano, L. (2016): Universal screening increases the representation of low-income and minority students in gifted education, PNAS, 113(48), 13678-13683.
Assouline, S.G., Foley Nicpon, M. and Dockery, L. (2012): Predicting the academic achievement of gifted students with autism spectrum disorder, Journal of Autism and Developmental Disorders, 42(9), 1781-1789.
Alonso Benito, S. et al. (2026): Reading and writing profiles in twice-exceptional adolescents with intellectual giftedness and dyslexia, Journal of Intelligence, 14(6), 108.
Almulhim, N. et al. (2026): Hidden potential: an exploratory study of the prevalence of twice-exceptional students in Saudi Arabia, Journal of Intelligence, 14(5), 83.
Benson, N.F. et al. (2026): Redefining specific learning disabilities: an attempt to bridge research, policy, and practice through expert consensus, Journal of School Psychology, 116, 101549.
Lovett, B.J. and Lewandowski, L.J. (2006): Gifted students with learning disabilities: who are they?, Journal of Learning Disabilities, 39(6), 515-527.

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Understanding IQ

Signs of a Gifted Child

The "reads early, has a big vocabulary" checklist misses what a 2024 systematic review actually found: an uneven cognitive profile, a documented speed-accuracy tradeoff, asynchronous development, and real gaps in who gets identified. What the research says, and what to do with a hunch.

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Understanding IQ

High IQ and ADHD

High IQ and ADHD can and do coexist, at close to the general-population rate. What twice-exceptional actually means, why the combination gets missed in both directions, and how ADHD can pull down a full-scale IQ score without touching real reasoning ability.

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IQ Testing for Children

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