Anxiety and IQ: What the Research Shows About Anxiety Disorders, Worry and Intelligence

Anxiety and IQ are only weakly linked, and the average link runs opposite to the popular claim: people who report more anxiety tend to score slightly lower on intelligence tests, and children with lower IQ scores are somewhat more likely to develop anxiety disorders as adults. The correlation is small, about -0.1, so many highly anxious people score well above average and many calm people score below it.

This article covers the size of that correlation, the long-term cohort studies, where the idea that "anxiety is a sign of intelligence" comes from, and how an anxiety disorder can affect performance on particular subtests. It is about anxiety disorders and anxious temperament. Nervousness during the test session itself is a separate subject, covered under test anxiety in our article on factors that affect your IQ test results.

Researchers separate "trait anxiety," a stable tendency to feel worried or tense across many situations, from "state anxiety," which is how anxious a person feels at a given moment. Trait anxiety is one facet of the broader personality trait called neuroticism.

The largest synthesis of this question is a meta-analysis by Anglim and colleagues, which pooled 272 samples and more than 160,000 people. Neuroticism correlated about -0.09 with intelligence, and the anxiety facet of neuroticism showed a correlation of similar size. Openness to experience (about 0.20) was the only Big Five trait with a stronger link.

A correlation of -0.09 means anxiety accounts for less than 1% of the differences in people's IQ scores. Knowing how anxious someone is tells you almost nothing about how they will score. The authors also point out that most of the underlying studies were low-stakes research sessions, where nerves are less likely to drag performance down, and they suggest the small negative link may be real and not just a testing artifact. One explanation they raise is that higher intelligence may give people more resources for managing worry and fear.

Correlations measured at one point in time cannot show which came first. Long-running birth cohorts can, because IQ is measured in childhood, years before most anxiety disorders begin.

In the Dunedin study in New Zealand, Koenen and colleagues tested 1,037 children born in 1972 and 1973 with the WISC-R at ages 7, 9 and 11, then made psychiatric diagnoses at ages 18, 21, 26 and 32. The findings for anxiety were:

• Any anxiety disorder: Each 15-point (one standard deviation) increase in childhood IQ went with a 26% reduction in the odds of an adult anxiety disorder diagnosis. At age 32, 32.5% of members with a childhood IQ of 85 or below had an anxiety disorder in the past year, compared with 14.9% of those with an IQ of 115 or above.

• Specific disorders: Higher childhood IQ predicted a 29% reduction in the odds of generalized anxiety disorder and a 40% reduction for social phobia (social anxiety disorder). There was no association with simple phobia, panic disorder or obsessive-compulsive disorder.

The results held after controlling for sex, childhood socioeconomic status, perinatal problems, low birth weight and childhood maltreatment. The researchers also reran the analysis using only IQ scores from ages 7 and 9, so that anxiety present at age 11 could not have depressed the scores, and the findings were the same.

A second prospective study points the same way. Gale and colleagues followed 3,258 U.S. Army veterans whose cognitive ability was measured at enlistment, at an average age of about 20, and who were assessed with a structured diagnostic interview at an average age of 38. For each one standard deviation lower ability score, the odds of current generalized anxiety disorder were 1.43 times higher, and most associations remained significant after adjustment for confounders. The same pattern for depression is discussed in our article on whether there is a link between IQ and depression.

The claim that anxious people are smarter traces mainly to two small studies and a survey of high-IQ society members. All of them are much weaker evidence than the cohorts above.

• The generalized anxiety disorder brain-imaging study: Coplan and colleagues compared 26 patients with generalized anxiety disorder and 18 healthy volunteers. The patient group had a higher average IQ on a brief Wechsler test (118.65 versus 109.44). Within the patient group, more worry went with higher IQ, while among the healthy volunteers, less worry went with higher IQ. The authors themselves noted that recruitment bias may explain why their patients scored so high. With 44 participants, this study cannot show anything about anxiety and IQ in the general population.

• The verbal intelligence and worry study: Penney, Miedema and Mazmanian tested 126 undergraduates. Verbal intelligence uniquely predicted more severe worry and rumination, while nonverbal intelligence predicted less "post-event processing," the habit of replaying social situations afterward. The positive links between verbal intelligence and anxiety or depression symptoms became non-significant once overlapping variables were controlled. University students also have a narrower IQ range than the general population.

The survey evidence is weaker still. Karpinski and colleagues surveyed 3,715 members of American Mensa and found higher self-reported rates of diagnosed or suspected mood and anxiety disorders than national statistics. Members chose whether to respond, "suspected" conditions were counted, and the comparison group was not tested the same way, so the result describes this sample and cannot establish that high IQ raises anxiety risk.

A fair reading is that verbal ability may shape what anxious thinking looks like. That is a much narrower claim than "anxiety means high intelligence," and the large population studies do not support the broad version.

Even if anxiety and ability are only weakly related, an active anxiety disorder can affect how a person performs on the day. The clearest evidence concerns "working memory," the ability to hold and manipulate information for a few seconds, which our article on what working memory is explains in more detail.

Moran's meta-analysis of 177 samples and 22,061 people found that self-reported anxiety was reliably related to poorer working memory performance, with an average effect size of -0.33. The effect was similar for simple span tasks such as digit span (-0.32), the type of task used in the working memory subtests of the Wechsler scales. This suggests that a person tested during a period of severe anxiety may score lower on working memory tasks than they would at a calmer time.

Anxiety disorders are diagnosed by clinicians such as psychologists and psychiatrists through interviews and standardized measures. An IQ test cannot diagnose an anxiety disorder, and anyone concerned about anxiety symptoms should speak with their doctor or a licensed mental health professional. Anxiety symptoms are also common in posttraumatic stress disorder, where research on IQ before and after trauma has developed in its own direction.

On average, no. Large studies find a small negative correlation of about -0.1 between anxiety and intelligence, and the "smarter" claim rests on small or self-selected samples.

Anxiety does not appear to lower underlying ability in any large way, but severe anxiety during testing can reduce performance on working memory tasks. In birth cohorts, lower childhood IQ comes before adult anxiety disorders, which suggests IQ is more often the earlier factor.

In the Dunedin cohort, each 15-point increase in childhood IQ went with 40% lower odds of social phobia in adulthood. This is a group-level association and does not predict any individual's risk.

One study of 126 undergraduates found that higher verbal intelligence predicted more worry and rumination. The finding has not been confirmed in large population samples.

No. An IQ test measures cognitive abilities, and anxiety disorders are diagnosed by a qualified clinician.

The research on anxiety and IQ points to a small negative relationship. People who report more anxiety score slightly lower on average, and children with lower IQ scores are somewhat more likely to develop generalized anxiety disorder or social anxiety as adults. The idea that anxiety signals high intelligence comes from small, selected samples, although verbal ability may influence how much a person worries. Because the correlation is so weak, a person's anxiety level says very little about their intelligence. If you want a score that reflects your abilities and reports its margin of error, take a professionally developed IQ test at a time when you feel settled.

1. Anglim, J., Dunlop, P. D., Wee, S., Horwood, S., Wood, J. K., & Marty, A. (2022). Personality and intelligence: A meta-analysis. Psychological Bulletin, 148(5-6), 301-336. doi.org

2. Koenen, K. C., Moffitt, T. E., Roberts, A. L., Martin, L. T., Kubzansky, L., Harrington, H., Poulton, R., & Caspi, A. (2009). Childhood IQ and adult mental disorders: A test of the cognitive reserve hypothesis. American Journal of Psychiatry, 166(1), 50-57. doi.org

3. Gale, C. R., Deary, I. J., Boyle, S. H., Barefoot, J., Mortensen, L. H., & Batty, G. D. (2008). Cognitive ability in early adulthood and risk of 5 specific psychiatric disorders in middle age: The Vietnam Experience Study. Archives of General Psychiatry, 65(12), 1410-1418. doi.org

4. Coplan, J. D., Hodulik, S., Mathew, S. J., Mao, X., Hof, P. R., Gorman, J. M., & Shungu, D. C. (2012). The relationship between intelligence and anxiety: An association with subcortical white matter metabolism. Frontiers in Evolutionary Neuroscience, 3, Article 8. doi.org

5. Penney, A. M., Miedema, V. C., & Mazmanian, D. (2015). Intelligence and emotional disorders: Is the worrying and ruminating mind a more intelligent mind? Personality and Individual Differences, 74, 90-93. doi.org

6. Karpinski, R. I., Kinase Kolb, A. M., Tetreault, N. A., & Borowski, T. B. (2018). High intelligence: A risk factor for psychological and physiological overexcitabilities. Intelligence, 66, 8-23. doi.org

7. Moran, T. P. (2016). Anxiety and working memory capacity: A meta-analysis and narrative review. Psychological Bulletin, 142(8), 831-864. doi.org

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