Anxiety and IQ: How Anxiety Affects Intelligence Test Scores
Anxiety disorders — including Generalized Anxiety Disorder (GAD), Social Anxiety Disorder, Panic Disorder, and OCD — are the most common class of mental health conditions, affecting approximately 18% of adults in the United States alone. Anxiety involves excessive fear, worry, and physiological arousal that interferes with daily functioning. Cognitive science has clearly established that anxiety interferes with optimal cognitive performance, particularly on tasks requiring working memory, executive function, and performance under pressure. The mechanisms are well understood: elevated cortisol and adrenaline, attentional hijacking by threat-related stimuli, and the deployment of cognitive resources toward monitoring for danger — all of which reduce the resources available for problem-solving. This makes IQ testing one of the most anxiety-prone environments imaginable for people with anxiety disorders.
How Anxiety Disorders Affects IQ Test Performance
Anxiety primarily impairs IQ test performance through working memory interference — anxious individuals use a significant portion of their working memory capacity to monitor for threats, ruminate about performance, and process physiological anxiety signals, leaving less capacity for the actual test questions. This effect is strongest on Working Memory subtests (Digit Span, Letter-Number Sequencing) and Processing Speed subtests performed under time pressure. Research shows that the performance gap between anxious and non-anxious individuals is largest on the most difficult items — where working memory demand is highest — and smallest on easy items where cognitive load is low. Social anxiety additionally impairs performance in one-on-one testing with an examiner. Test anxiety specifically, even in non-anxious individuals, can reduce IQ scores by 10–15 points compared to performance in low-stakes conditions.
What the Research Shows
A foundational study by Michael Eysenck's Attentional Control Theory demonstrated that anxiety impairs the efficiency of working memory through intrusive thought monitoring, with the effect proportional to anxiety severity. A 2021 meta-analysis in Clinical Psychology Review found that anxiety disorders were associated with working memory impairments equivalent to 0.5–0.7 standard deviations — roughly 7–10 IQ points — with the largest effects in high-demand cognitive tasks. Research by Sian Beilock (now president of Dartmouth College) showed that high-working-memory individuals — typically the highest performers — suffer the most from test anxiety because they have more 'cognitive horsepower' available to be hijacked by worry. A 2019 study in Psychological Science found that students with high math anxiety showed processing speed and accuracy reductions equivalent to significant IQ decreases on timed mathematics assessments, with performance recovering substantially in untimed conditions.
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Frequently Asked Questions
Can anxiety make you score lower on an IQ test?
Yes, significantly. Research consistently shows that anxiety reduces performance on IQ tests, particularly on timed Working Memory and Processing Speed subtests. The mechanism is well-established: anxiety hijacks working memory resources for threat monitoring, leaving less capacity for problem-solving. The effect can be 7–15 IQ points in people with moderate-to-severe anxiety disorders. This means IQ test scores obtained during acute anxiety may substantially underestimate a person's true cognitive ability.
Does high intelligence protect against anxiety?
Research suggests the opposite may be true. Highly intelligent people appear to experience anxiety at higher rates, possibly because they can anticipate more possible negative outcomes, engage in more extensive rumination, and are more sensitive to complexity and contradiction. A 2016 study found that high verbal IQ was associated with both more adaptive and more maladaptive worry — suggesting intelligence amplifies the anxiety tendency rather than buffering it.
What's the difference between test anxiety and an anxiety disorder?
Test anxiety is a situational fear specifically triggered by evaluative settings like exams or IQ tests. Anxiety disorders involve pervasive, chronic anxiety that extends across situations and significantly impairs daily functioning. Both can reduce IQ test performance, but anxiety disorders typically cause broader and more consistent cognitive impairment. Test anxiety is extremely common (estimated to affect 25–40% of students) and represents the single largest source of bias in standardized cognitive assessment.
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MyIQScores Editorial Team
Researchers in cognitive psychology, psychometrics & educational science
Last updated
May 10, 2026
All content on MyIQScores is reviewed for scientific accuracy against peer-reviewed research in cognitive psychology and psychometrics. Our editorial team cross-references each article with published literature before publication and updates pages whenever new research warrants a revision.