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

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Sleep and IQ

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Taking a Test

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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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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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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KBIT-2 Test

Posted on October 5, 2026 by Mahesh

Scores & Scales

KBIT-2 Test: Subtests, Scores and What the Kaufman Brief Intelligence Test Measures

The KBIT-2 is a 20-minute IQ screen for ages 4 to 90 with three subtests: Verbal Knowledge, Riddles and Matrices. See how its scores work, what the 2022 KBIT-2 Revised changed, how closely it matches the WISC-V and KABC-II, and why it is a screen rather than a full evaluation.

By Leon Falkner, Data & Research AnalystPublished October 5, 2026 · 8 min readReviewed by Aarav Vardhan, Editor-in-Chief

Three cards about the KBIT-2. Three subtests, three scores: Verbal Knowledge and Riddles plus Matrices, for ages 4 to 90, in about 20 minutes, giving Verbal, Nonverbal and IQ Composite standard scores with a mean of 100 and a standard deviation of 15. Revised in 2022: the revision uses norms from 2021 data, while the first edition used data collected in 2002 to 2003. Agreement with longer tests: Pearson reports a correlation of .77 between the revised IQ Composite and the KABC-II NU, and an independent study of 101 children found .72 with the WISC-V but wide error in predicting individual scores.

The KBIT-2 (Kaufman Brief Intelligence Test, Second Edition) is a brief IQ screening test, given one-to-one by a trained examiner in about 20 minutes, for people aged 4 to 90. It has three subtests, Verbal Knowledge and Riddles for crystallized (verbal) ability and Matrices for fluid (nonverbal) ability, and it reports Verbal, Nonverbal and IQ Composite standard scores with a mean of 100 and a standard deviation of 15. Pearson published a revised edition, the KBIT-2 Revised, in 2022, with norms built from 2021 data. Its job is screening: Pearson’s own technical report says a longer test such as the WISC-V is the next step when screening results warrant it. This guide covers the subtests, what changed in the revision, how scores are reported, how well the KBIT-2 agrees with longer tests and who can give it.

What it is: a brief, individually administered intelligence screen; about 20 minutes; ages 4:0 to 90:0; qualification level B at Pearson.
Subtests and scores: Verbal Knowledge and Riddles feed the Verbal (crystallized) score; Matrices is the Nonverbal (fluid) score; all three make the IQ Composite.
Scale: standard scores with a mean of 100 and an SD of 15, plus percentile ranks by age.
The revision: KBIT-2 Revised (2022), norms from 2021 data; the first edition used data collected in 2002 to 2003.
Accuracy: Pearson reports r = .77 between the revised IQ Composite and the KABC-II NU; an independent study of 101 children found r = .72 with the WISC-V FSIQ but wide error for single scores.

What is the KBIT-2?

The KBIT-2 succeeded the original K-BIT and is published by Pearson, the same publisher as the Wechsler scales. It is meant for the situations where a long evaluation is not practical. Pearson’s technical report describes the demand directly: school psychologists face increasingly multifaceted evaluations, and in some settings practitioners routinely give a brief test like the KBIT-2 Revised to screen for cognitive issues, then a more comprehensive test, such as the KABC-II NU, the WISC-V or the Woodcock-Johnson IV Tests of Cognitive Abilities, if screening indicates more testing is warranted. For how brief tests compare on time, see our guide to how long an IQ test takes.

What are the KBIT-2 subtests?

The three KBIT-2 subtests
Subtest	What the examinee does	Feeds which score
Verbal Knowledge	Looks at pictures in a stimulus book and shows or says what fits a word or question, a vocabulary and general-knowledge task	Verbal (crystallized)
Riddles	Listens to a short riddle read aloud and answers with a word	Verbal (crystallized)
Matrices	Looks at a pattern or picture grid with a piece missing and picks the response that completes it	Nonverbal (fluid)

Pearson describes Verbal Knowledge and Riddles as assessing crystallized ability, the store of words and knowledge a person has accumulated, and Matrices as a measure of nonverbal fluid reasoning. It adds that gifted and talented centers use Matrices as a standalone measure of nonverbal fluid reasoning. Fluid reasoning is the same ability that working-memory training claims aim at; see our dual n-back guide for the evidence on that, our executive function vs IQ guide for which control abilities track it, and our fluid vs crystallized intelligence guide for the distinction. Matrices items work like the ones in Raven’s matrices.

The KBIT-2 Revised shares design with a longer test: its Verbal Knowledge and Riddles subtests were built as parallel forms of the same-named subtests in the KABC-II Normative Update. Pearson says that when both tests are needed, substituting the KBIT-2 Revised scores into the KABC-II NU saves about 10 to 20 minutes and avoids repeating the same task, which could distort scores through procedural learning, changed effort or regression to the mean.

What changed in the KBIT-2 Revised?

Pearson released the revision in 2022. Its own side-by-side sheet and FAQ list the changes:

New norms. The revision is based on 2021 data collection, with one norm for in-person and remote administration. The original KBIT-2 data were collected in 2002 and 2003.
Refreshed items. Outdated drawings were replaced on several Verbal Knowledge items, and items were updated for auditory issues, diversity and alternate correct responses, with the target concepts left unchanged.
Matrices. Pearson dropped an item that showed a book of matches because young children are not exposed to matches, after finding it could go with no effect on reliability, and added newly designed difficult items to extend the upper range.
Riddles. Modern answers were added to the scoring responses, five items were dropped for diversity and bias concerns and two difficult items were added, making the subtest shorter.
Scoring. Q-global scoring is now an option, and the scores come with 90% and 95% confidence intervals.
Materials. The Manual and Record Form changed, so the two editions’ materials are not interchangeable, but Pearson says the overall scoring and administration procedures stay familiar.

How are KBIT-2 scores reported?

The KBIT-2 reports three scores, Crystallized (Verbal), Fluid (Nonverbal) and IQ Composite, as standard scores with a mean of 100 and a standard deviation of 15, along with percentile ranks by age. The table below shows what those standard scores mean on the normal curve; the published percentile ranks come from Pearson’s own norm tables and can differ slightly from the smooth curve.

Standard scores and percentiles on a mean-100, SD-15 scale
Standard score	Percentile (normal curve)	Our guides
70	2.3%	See IQ classifications
85	15.9%	See the percentile calculator
100	50%	The average by definition
115	84.1%	See IQ classifications
130	97.7%	See gifted cut-off scores

Because the KBIT-2 is short, a single score carries more uncertainty than a full scale; Pearson reports confidence intervals for that reason. If you want to compare against a scale with a different standard deviation, our SD 15 vs SD 16 guide shows the conversion.

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How well does the KBIT-2 agree with longer IQ tests?

Pearson’s KBIT-2 Revised and KABC-II NU technical report (Table 1.1) correlates the two tests. The KBIT-2 Revised IQ Composite correlates .77 with the KABC-II NU Fluid-Crystallized Index and .67 with its Mental Processing Index. The Verbal score correlates .87 with the KABC-II Knowledge/Gc scale. The Matrices-based Nonverbal score correlates .61 with Pattern Reasoning and .52 with the Planning/Gf scale, lower than the verbal link, and the same-named Verbal Knowledge and Riddles subtests correlate .75 across the two tests. These are the publisher’s own numbers.

An independent look at the original KBIT-2 comes from Cheng and colleagues (2024), who reviewed records of 101 children with developmental disorders at a children’s hospital in Singapore. The KBIT-2 IQ Composite correlated r = .722 with WISC-V Full Scale IQ and r = .648 with WPPSI-IV Full Scale IQ. Regression analysis showed that KBIT-2 scores tended to underestimate or overestimate Wechsler scores, with the highest variability for the Nonverbal IQ against the WISC-V Fluid Reasoning Index (error limits −53.1 to 39.7). The authors concluded that the KBIT-2 has good concurrent validity and is a good screening tool in this group, and that more studies are needed before it is used for diagnostic decisions or special-education placement.

Squared, a correlation of .72 means the two tests share about 52% of their variance, and .77 about 59%. That is strong enough for screening and not strong enough to treat a KBIT-2 score as a stand-in for a full Wechsler result. Our guides to the WPPSI-IV, the WISC-V, the Stanford-Binet and the Woodcock-Johnson cover the longer instruments.

Who gives the KBIT-2, and can you take it online?

It is a professional test, not an online quiz. Pearson lists the KBIT-2 Revised at qualification level B, one level below the level C that Wechsler scales need (see how an official IQ test works), and it is administered by a trained examiner using a stimulus book. Pearson’s comparison sheet lists administration in person and remotely for the revised edition, with digital stimulus books and the manual on Q-global, and the product page lists a Spanish version and telepractice guidance. A page or PDF online that calls itself the KBIT is not the test, because the items and norms are the publisher’s. If what you want is a score on the IQ scale from home, our IQ test is built for that.

When is a brief test enough?

For screening, to find out whether a longer evaluation is worth the time, a brief test does its job, and that is how Pearson positions it. For decisions with consequences, such as a school placement or a disability determination, the longer instruments are the usual next step, and the Singapore authors above say more research is needed before the KBIT-2 supports such decisions. Gifted programs are a nuance: Matrices alone is used by some centers as a nonverbal measure, but a cut-off score on any single test has an interval around it; our gifted cut-off scores guide and guide to IQ testing for children explain how those decisions are made.

Quick answers

What is the KBIT-2 test? The Kaufman Brief Intelligence Test, Second Edition: a brief, individually administered intelligence screen from Pearson.
What does the KBIT-2 measure? Verbal (crystallized) ability through Verbal Knowledge and Riddles, and nonverbal (fluid) ability through Matrices, combined into an IQ Composite.
How long does the KBIT-2 take? About 20 minutes, according to Pearson.
What ages is the KBIT-2 for? 4 years 0 months to 90 years 0 months.
What is the KBIT-2 Revised? A 2022 update with norms from 2021 data, refreshed items, new hard items in Matrices and Riddles, and Q-global scoring.
What scale does the KBIT-2 use? Standard scores with a mean of 100 and a standard deviation of 15.
Is the KBIT-2 as accurate as the WISC-V? It correlated .72 with WISC-V Full Scale IQ in one independent study, with wide error for single scores; it is a screen, not a replacement.
Can I take the KBIT-2 online? No. A trained examiner gives it; Pearson sells it at qualification level B.

Sources

Pearson Assessments: Kaufman Brief Intelligence Test, Second Edition Revised (KBIT-2 Revised), product page: age range, scores, qualification level, completion time and norms.
Pearson: KBIT-2 Revised comparison sheet (what changed, side by side), 2022.
Pearson: KBIT-2 Revised FAQs (publication, compatibility, scoring and administration).
Pearson: KBIT-2 Revised and KABC-II NU Technical Report (correlations in Table 1.1, the substitution studies and the screening rationale).
Cheng, A.S.M. et al. (2024): Concurrent validity of intelligence assessments in children with developmental disabilities in an Asian setting: comparison of the Kaufman brief intelligence test – Second edition with the Wechsler Intelligence Scales, Pediatrics & Neonatology, 65(4), 341-347.

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Taking a Test

Professional IQ Tests

When a psychologist measures intelligence, they reach for one of a small number of standardised instruments. This guide covers what the Wechsler scales, Stanford-Binet, Woodcock-Johnson and Raven’s Progressive Matrices each measure, who each one is for, and where an online test genuinely fits.

August 27, 20266 min read

Taking a Test

How Long Does an IQ Test Take?

An official IQ test usually takes 45 to 90 minutes of testing: 45 for the WAIS-5, 60 to 90 for the WAIS-IV, 12 for the Wonderlic. See the time for every major test, how many questions to expect, why two people take different amounts of time and what a full evaluation adds.

September 30, 202610 min read

Scores & Scales

WPPSI-IV Test

The WPPSI-IV test covers ages 2:6 to 7:7 in two bands, with 15 subtests, five index scores and a Full Scale IQ. See what each subtest asks, how a published sample report reads, how the score labels work, and what a preschool score can and cannot tell parents.

September 26, 202610 min read

Can a Concussion Lower Your IQ?

Posted on October 5, 2026 by Mahesh

Research & Evidence

Can a Concussion Lower Your IQ? What the Meta-Analyses Show

Can a concussion lower your IQ? Meta-analyses of mild and severe head injury show scores dip in the first days, recover within weeks for most people and stay lower after moderate or severe injury. See the effect sizes in IQ points, why clinic samples look worse and why a baseline is rarely available.

By Leon Falkner, Data & Research AnalystPublished October 5, 2026 · 8 min readReviewed by Aarav Vardhan, Editor-in-Chief

A bar chart of effect sizes, Cohen's d, from published meta-analyses of head injury and cognitive scores. Mild traumatic brain injury, delayed memory in the first 3 months: 1.03. Moderate-severe injury across all follow-up periods: 0.74. Mild injury, all domains pooled: 0.54. Mild head injury across all follow-up periods: 0.24. Two or more concussions versus one in athletes: 0.06. Mild injury after 3 months in unselected or prospective samples: 0.04. On an IQ scale, d of 1.0 is 15 points; these are averages across cognitive tests, not IQ scores.

Can a concussion lower your IQ? For most people a single concussion does not leave a lasting drop, but the effect is real in the first days and weeks, and it is larger and longer-lasting after moderate or severe brain injury. A meta-analysis of 39 studies of mild traumatic brain injury (1,463 cases and 1,191 controls) found a moderate overall effect on cognitive tests (d = .54) that had disappeared by 3 months in unselected or prospective samples (d = .04). For sports concussion, a 21-study analysis found no residual impairment when testing was done more than 7 days after injury. Moderate-to-severe brain injury is different: it averages d = −0.74 and remains markedly impaired beyond 2 years. This guide turns those effect sizes into IQ points, explains why clinic samples look worse than community samples, and shows why a true before-and-after IQ comparison is rare.

Most single concussions: cognitive scores recover within weeks. In unselected or prospective samples, mild injury showed no residual effect by 3 months (d = .04).
The first days: the biggest effects are on memory and global cognitive functioning; after a sports concussion, no residual impairment was found when testing was done beyond 7 days.
Who you sample matters: at 3 months or later, clinic-based samples showed d = .74 and litigation samples d = .78, against .04 in unselected samples.
Repeated concussions: across 8 athlete studies, overall d = .06, with poorer delayed memory and executive functioning.
Moderate and severe injury: d = −0.74 on average, more than three times the mild-injury figure, and still markedly impaired more than 2 years after injury.

What counts as a concussion, and how is it different from a severe brain injury?

A concussion is commonly defined as a mild traumatic brain injury (MTBI): a blow or jolt that briefly disrupts how the brain works, with symptoms such as confusion, headache, dizziness or gaps in memory. Clinicians grade traumatic brain injury (TBI) as mild, moderate or severe, mainly by the Glasgow Coma Scale, how long consciousness was lost and how long memory was affected. The research below keeps the groups apart because they behave differently, and because a concussion and a severe injury are different questions. These studies did not measure a place on the IQ classification scale; they measured performance on cognitive tests.

What happens to cognitive scores in the first days and weeks?

Belanger and Vanderploeg (2005) pooled 21 studies of sports-related concussion (790 cases, 2,014 controls) and found an overall effect of d = 0.49. Within 24 hours of injury the effects were largest for delayed memory (d = 1.00), memory acquisition (1.03) and global cognitive functioning (1.42). Beyond 7 days after injury, they found no residual neuropsychological impairment, although delayed memory in studies with a control group was still a problem at 7 days. Using athletes with a history of prior head injury appeared to inflate the effect sizes for the current concussion.

Belanger and colleagues (2005) found the same shape in non-sports mild TBI across 39 studies: the acute effects (under 3 months) were greatest for delayed memory (d = 1.03) and fluency (d = .89). Schretlen and Shapiro (2003) add that the natural logarithm of the follow-up interval correlated very strongly with the effect size after mild head injury, and that overall cognitive functioning “recovers most rapidly during the first few weeks” and essentially returns to baseline within 1 to 3 months.

Effect sizes in the published meta-analyses
Group and timing	Cohen d	IQ points at SD 15	Source
Sports concussion, first 24 hours, global cognitive functioning	1.42	21	Belanger and Vanderploeg 2005
Mild TBI, under 3 months, delayed memory	1.03	15	Belanger et al. 2005
Mild TBI, under 3 months, fluency	0.89	13	Belanger et al. 2005
Moderate-severe TBI, all follow-up periods	0.74	11	Schretlen and Shapiro 2003
Mild TBI, all studies and domains	0.54	8	Belanger et al. 2005
Sports concussion, all studies	0.49	7	Belanger and Vanderploeg 2005
Mild head injury, all follow-up periods	0.24	4	Schretlen and Shapiro 2003
Two or more concussions vs one (athletes)	0.06	1	Belanger et al. 2010
Mild TBI, 3+ months, unselected or prospective samples	0.04	less than 1	Belanger et al. 2005

Read the third column with care. It simply multiplies d by 15 to show the size on the familiar IQ scale (see SD 15 vs SD 16). The effect sizes themselves are group averages across cognitive tests, mostly memory, attention and executive measures, not full-scale IQ scores, and an average hides individuals who recover slowly or fast.

What happens after 3 months?

This is where the headline numbers split. In unselected or prospective samples, Belanger and colleagues found no residual neuropsychological impairment by 3 months after mild TBI (d = .04). In clinic-based samples and in samples that included people in litigation, the effects at 3 months or later were larger (d = .74 and .78), and litigation was associated with cognitive functioning that stayed the same or got worse over time. The abstract does not give the reasons, and we will not guess at any one person’s. What it shows is that the lingering effect you read about depends heavily on who was sampled: people drawn from the community and followed from the injury had recovered on average, and people who came through clinics or legal claims showed larger effects. A person who still has trouble months later deserves a proper assessment either way.

Do repeated concussions lower IQ?

Belanger, Spiegel and Vanderploeg (2010) pooled 8 studies, all of athletes, comparing 614 people with more than one self-reported mild TBI against 926 with just one. The overall effect was minimal and not significant (d = 0.06), but a history of multiple self-reported concussions went with poorer delayed memory and executive functioning. The samples were athletes tested after self-reported histories, so the result cannot speak for people outside sport or for those with severe injuries.

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What about moderate and severe injuries, and children?

Schretlen and Shapiro (2003) pooled 39 mostly cross-sectional studies (48 comparisons; 1,716 patients and 1,164 controls). Averaged across follow-up periods, the effect of moderate-severe TBI (d = −0.74) was more than three times the effect of mild head injury (d = −0.24). Cognitive functioning improved over the first two years after moderate-severe TBI but remained markedly impaired among patients tested more than 2 years after injury.

For children, Babikian and Asarnow (2009) summarized 28 publications from 1988 to 2007. In severe pediatric TBI they report moderate to very large impairments in intellectual functioning, mainly performance IQ, with substantial recovery in longitudinal studies, especially for performance relative to verbal IQ, although by the longest follow-up the severe group showed impairments in all the domains the review covered. For children with moderate TBI they say some deficits persist beyond two years compared with matched peers. Index scores such as processing speed matter in these evaluations; our guide to processing speed and IQ explains what that index measures.

If nobody tested your IQ before, how can anyone tell it dropped?

Usually they cannot, directly. Few people have a baseline IQ score from before an injury, so clinicians estimate premorbid ability from skills that hold up, such as reading irregular words aloud. The best-known example is the National Adult Reading Test (NART). In a study by McGurn and colleagues (2004), an IQ test taken at age 11 correlated r = .63 with NART scores at about age 80 in people who had developed dementia and r = .60 in those who had not, and after controlling for age-11 IQ, mean NART scores did not differ between the groups. That study was about dementia; clinicians apply the same logic after brain injury, with reading tests such as the NART or Pearson’s WTAR and TOPF.

A correlation of .60 explains about 36% of the variance (r squared), so a reading-based estimate is a range, not a number, and a drop of a few points will not stand out against it. Our guides to whether an IQ test can detect dementia and how long an IQ result stays valid cover the same limits from other angles. Brief tests also have a role in these evaluations; see our KBIT-2 guide for one example of a short IQ screen.

What should you do if you are worried?

If symptoms continue longer than expected after a head injury, or a child’s schoolwork changes, ask a physician about a neuropsychological evaluation. An online IQ quiz cannot separate injury from effort, mood, sleep, pain or medication, and it cannot show change without a baseline; what it can tell you is described in our guide to whether IQ tests are reliable. Attention and executive-control tasks, such as the Stroop test (see also our executive function vs IQ guide), are part of the toolkit clinicians use alongside IQ tests, not a substitute for them.

Quick answers

Can a concussion lower your IQ? Temporarily, yes: cognitive scores dip in the first days and weeks. In unselected samples there was no residual effect by 3 months after mild injury.
Does a concussion cause a lasting drop in cognitive scores? Not in group averages for most single concussions, but clinic-based samples show larger long-term effects and moderate-severe injuries do.
How long does it take cognitive function to recover after a concussion? For sports concussion, no residual impairment was found beyond 7 days; for non-sports mild TBI, by about 3 months.
Do multiple concussions lower IQ? Overall d = .06 across 8 athlete studies, with poorer delayed memory and executive functioning.
How many IQ points is a d of 0.5? About 7.5 points on a 15-point scale, but these are cognitive-test averages, not IQ scores.
How do doctors know your IQ before a head injury? They usually estimate it from reading tests such as the NART, which correlated about .60 with age-11 IQ.

Sources

Belanger, H.G., Curtiss, G., Demery, J.A., Lebowitz, B.K. and Vanderploeg, R.D. (2005): Factors moderating neuropsychological outcomes following mild traumatic brain injury: a meta-analysis, Journal of the International Neuropsychological Society, 11(3), 215-227.
Belanger, H.G. and Vanderploeg, R.D. (2005): The neuropsychological impact of sports-related concussion: a meta-analysis, Journal of the International Neuropsychological Society, 11(4), 345-357.
Belanger, H.G., Spiegel, E. and Vanderploeg, R.D. (2010): Neuropsychological performance following a history of multiple self-reported concussions: a meta-analysis, Journal of the International Neuropsychological Society, 16(2), 262-267.
Schretlen, D.J. and Shapiro, A.M. (2003): A quantitative review of the effects of traumatic brain injury on cognitive functioning, International Review of Psychiatry, 15(4), 341-349.
Babikian, T. and Asarnow, R. (2009): Neurocognitive outcomes and recovery after pediatric TBI: meta-analytic review of the literature, Neuropsychology, 23(3), 283-296.
McGurn, B. et al. (2004): Pronunciation of irregular words is preserved in dementia, validating premorbid IQ estimation, Neurology, 62(7), 1184-1186.

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Diagram showing where processing speed sits in the structure of cognitive ability, with simple reaction time, choice reaction time and inspection time on one axis and their differing strength of association with general intelligence shown alongside

Understanding IQ

Processing Speed and IQ

Fast thinkers are assumed to be smart thinkers, and there is a real finding underneath the stereotype: people who score higher on IQ tests do respond faster on tasks with no reasoning content at all. But the link is weaker than the folklore, and on a professional battery the speed index is the least g-loaded.

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Taking a Test

Can an IQ Test Detect Dementia?

A standard IQ test cannot diagnose dementia; it has no personal baseline and was not built to screen for decline. How the MMSE and the more sensitive MoCA compare, why a normal score can hide early decline, and what actually helps catch it.

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Taking a Test

How long is IQ test valid?

Do you want to know how long an IQ test is valid for? Have you ever wondered how accurate it is and how it affects your IQ? Stop searching now. To better understand the significance of IQ test results, this article will investigate the validity period of these assessments.

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Walking Speed and IQ

Posted on October 5, 2026 by Mahesh

Research & Evidence

Walking Speed and IQ: What the Gait Research Shows

Walking speed and IQ are linked: in 904 adults aged 45, higher full-scale IQ went with faster walking (0.38). See what else went with gait speed, why childhood brain health at age 3 mattered, what walking speed predicts in older adults and why it is a health marker, not an IQ test.

By Arjun Vardhan, News & Research WriterPublished October 5, 2026 · 7 min readReviewed by Aarav Vardhan, Editor-in-Chief

A bar chart of standardized associations with gait speed in 904 adults aged 45 in the Dunedin study, adjusted for sex. Full-scale IQ at 45 measured with the WAIS-IV: 0.38. Grip strength: 0.36. Chair-stand test: 0.34. Neurocognitive health at age 3: 0.26. Total brain volume: 0.15. Cortical thickness: 0.09. These are associations, not proof of cause.

Walking speed and IQ are related: in a New Zealand cohort of 904 adults aged 45, people with a higher full-scale IQ walked faster, with a standardized association of 0.38 (95% CI 0.32 to 0.44). That was larger than the association with total brain volume (0.15), and poor neurocognitive functioning measured as early as age 3 also predicted slower walking in midlife (0.26). It is an association measured at one point in adulthood. It does not show that walking faster raises IQ, or that a slow walker has a low IQ. Gait speed seems to work as a marker of general physical and brain health. This guide covers what the study measured, what else walking speed went with, what it predicts in older adults and how to read the numbers.

The study: Dunedin cohort, 904 adults at age 45; gait speed measured three ways (usual pace, walking while reciting letters, maximum pace).
The IQ link: full-scale WAIS-IV IQ was associated with a composite gait speed at 0.38; each of the four WAIS-IV indexes was also associated (all P < .001).
Beyond IQ: grip strength (0.36), the chair-stand test (0.34), a faster pace of aging (−0.33) and childhood neurocognitive health at age 3 (0.26) all went with gait speed.
Older adults: across 9 cohorts of 34,485 people aged 65 and over, each 0.1 m/s faster gait was associated with a hazard ratio for death of 0.88 (Studenski et al., 2011).
The catch: an association at one time point; gait speed was not measured before age 45.

What did the Dunedin study find?

Rasmussen and colleagues (2019) used the Dunedin Multidisciplinary Health and Development Study, a population-based 1972 to 1973 birth cohort in New Zealand. Of 1,037 original participants, 997 were alive at 45, and 904 (90.7%) had their walking speed measured. Walking was timed under three conditions: usual pace from a standing start; the same pace while reciting alternate letters of the alphabet aloud (dual-task gait); and as fast as safely possible. The means were 1.30 meters a second (SD 0.17) for usual gait, 1.16 (SD 0.23) for dual-task gait and 1.99 (SD 0.29) for maximum gait. The three conditions were combined into a composite gait speed.

At 45, each person also took the WAIS-IV, which gives a full-scale IQ (mean 100.1, SD 14.9 in this cohort) and four index scores: processing speed, working memory, perceptual reasoning and verbal comprehension. Higher full-scale IQ went with faster composite gait, with a standardized regression coefficient of 0.38 (95% CI 0.32 to 0.44). For full-scale IQ the coefficients ranged from 0.23 to 0.39 across the individual walking conditions, and each of the four indexes was also associated with gait speed (all P < .001). The authors adjusted for sex, and report further adjustments for leg length, body composition and childhood socioeconomic status in supplementary tables.

What else goes with a slower walk?

IQ was one of many correlates, which is the main point. Gait speed also went with physical function, biological aging and brain structure, as the table shows. The authors’ conclusion is that gait speed is associated with more than geriatric functional status; it is also associated with midlife aging and lifelong brain health.

Standardized associations with gait speed at 45
Measure	Coefficient	Direction
Full-scale IQ at 45	0.38	higher IQ, faster walking
Grip strength	0.36	stronger grip, faster walking
Chair-stand performance	0.34	better performance, faster walking
2-minute step test	0.33	better performance, faster walking
Pace of biological aging	−0.33	faster aging, slower walking
Balance	0.28	better balance, faster walking
Self-reported physical limitations	−0.27	more limitations, slower walking
Neurocognitive functioning at age 3	0.26	poorer functioning, slower walking in midlife
Visual-motor coordination	0.24	better coordination, faster walking
Total brain volume	0.15	smaller volume, slower walking
Cognitive change from childhood to 45	0.10	greater decline, slower walking
Cortical thickness	0.09	more thinning, slower walking

The childhood results matter most for interpretation. A composite of neurocognitive functioning at age 3, built from a 45-minute exam that included a pediatric neurologist, standardized tests of intelligence, language and motor skills, and ratings of emotional and behavioral regulation, predicted walking speed four decades later (0.26). Cognitive decline from childhood to midlife also went with slower gait (0.10). For the speed side of WAIS-IV scores, see our guide to processing speed and IQ.

Does walking faster mean you have a higher IQ?

No, and the study does not claim it. The data are associations, and the authors list a clear limitation: they had no walking measurement before age 45 and no brain imaging before then, so they could not follow change over time. A person who walks faster is also, on average, stronger, better balanced and biologically younger in this cohort, which is why the authors describe gait speed as associated with midlife aging and lifelong brain health. Gait speed is better read as a broad marker than as a measure of intelligence: it does not tell you someone’s IQ, and it is not part of any IQ test.

Whether exercise itself changes cognitive scores is a different question, and a different kind of evidence. Our guide to exercise and IQ covers the trials.

Why would walking relate to the brain?

Walking looks automatic but draws on balance, sensory input and attention, which is one reason researchers add a mental task and watch what happens. In the Dunedin cohort, reciting letters aloud slowed the average walk from 1.30 to 1.16 meters a second, about 11%. The study does not isolate a mechanism, and we will not offer one; what it shows is that slower walking at 45 went, on average, with weaker brain, body and childhood indicators. The executive side of that dual-task burden is the subject of our guide to executive function vs IQ.

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What does walking speed predict in older adults?

Studenski and colleagues (2011) pooled individual data from 9 cohort studies of 34,485 community-dwelling adults aged 65 and over, followed for 6 to 21 years. The mean gait speed was 0.92 meters a second (SD 0.27), and there were 17,528 deaths. Gait speed was associated with survival in every study, with a pooled hazard ratio of 0.88 per 0.1 meters a second faster (95% CI 0.87 to 0.90). Survival increased across the whole range of speeds, and predictions from age, sex and gait speed were as accurate as predictions from age, sex, chronic conditions, smoking history, blood pressure, body mass index and hospitalization.

A 2016 meta-analysis by Beauchet and colleagues pooled 12 studies and found that poor gait performance, defined by standardized walking tests, predicted dementia: a pooled hazard ratio of 1.53 for any dementia, 1.79 for vascular dementia and 1.89 for non-Alzheimer dementias. The finding was weaker for Alzheimer disease (1.03). That is a statement about groups followed over time; a single slow walk is not a diagnosis. For what IQ tests can and cannot show about dementia, see our guide to whether an IQ test can detect dementia.

How should you read a walking-speed result?

Treat it as a health indicator, not an intelligence score. If walking has become slower or less steady, that is a reason to talk to a physician, whatever your IQ. If what you want to know is where you stand on the IQ scale, a walking test cannot tell you; a full test can, and the IQ test on this site or an official IQ test does. Our guide to the reaction time test covers another simple speed measure.

Quick answers

Are walking speed and IQ related? Yes, in one large cohort: full-scale IQ at 45 was associated with composite gait speed at 0.38 (95% CI 0.32 to 0.44).
Do people with a higher IQ walk faster? On average, in that study, yes, but it is an association, and many other things (strength, balance, aging, brain structure) went with gait speed too.
Does walking faster raise your IQ? The study cannot say. It measured both at one time point and had no earlier gait data.
What walking speeds did the studies record? In the Dunedin adults at 45, the mean usual pace was 1.30 meters a second; in pooled adults aged 65 and over, 0.92.
Does early childhood brain health predict adult walking speed? A composite of neurocognitive functioning at age 3, which included standardized tests of intelligence, predicted walking speed at 45 (0.26).
Does slow walking predict dementia? Poor gait predicted any dementia with a pooled hazard ratio of 1.53 in a 12-study meta-analysis, and Alzheimer disease only weakly (1.03).

Sources

Rasmussen, L.J.H. et al. (2019): Association of neurocognitive and physical function with gait speed in midlife, JAMA Network Open, 2(10), e1913123.
Studenski, S. et al. (2011): Gait speed and survival in older adults, JAMA, 305(1), 50-58.
Beauchet, O. et al. (2016): Poor gait performance and prediction of dementia: results from a meta-analysis, Journal of the American Medical Directors Association, 17(6), 482-490.

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Bar chart of aerobic exercise effects on four executive function skills, showing real improvements in inhibitory control, working memory and cognitive flexibility, and no significant change in planning

Mind & Everyday Life

Does Exercise Raise Your IQ?

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