Higher cognitive abilities and better educational outcomes during adolescence strongly predict a lower risk of developing mental health conditions later in life. A national survey of Norwegian men demonstrated that those with lower test scores and less schooling were significantly more likely to experience psychological distress in adulthood. The study was published in the journal Psychological Science.
Previous sociological research has demonstrated a strong association between educational attainment and overall mental health. Generally, people who earn advanced degrees experience fewer mood and anxiety disorders than people who leave school early. At the same time, academic success is closely related to an individual’s general cognitive abilities, including skills such as problem solving, numerical reasoning, and language comprehension.
This overlap leaves open questions about the root causes of these health disparities. The researchers wanted to know whether the increased risk of mental illness associated with leaving school early was actually driven by underlying cognitive characteristics. To answer this, researchers needed to simultaneously examine both cognitive test scores and educational attainment in a large, representative sample.
Historically, most psychological research relied on limited subsets of the population. People dealing with severe psychiatric problems or with low cognitive scores often drop out of long-term observational studies. This bias against healthy volunteers creates a biased understanding of health dynamics in the general public.
To overcome these selection problems, the team of researchers utilized a comprehensive national administrative database. Lead author Magnus Nordmo, a researcher at the University of Southeastern Norway, collaborated with researchers at the Norwegian Institute of Public Health, Duke University, and the University of Oslo. They aimed to uncover the distinct effects of teenage schooling and test performance on adult well-being.
The research team looked at the records of more than 270,000 Norwegian men born between 1970 and 1979. Military service was compulsory in Norway at the time, and young people were required to complete a standardized assessment of their mental capacity around the age of 18. The assessment measured fluid intelligence as well as accumulated knowledge using tasks including word comprehension, pattern recognition, and mathematical reasoning.
After standardizing military test scores, the researchers followed these people into midlife using national health registries. They examined primary care records of men between the ages of 36 and 40 to identify formal diagnoses of mental health conditions. These diagnoses include depression, anxiety, post-traumatic stress disorder, sleep disorders, substance abuse, schizophrenia, and more.
The team also accessed educational registration data to determine the highest level of schooling completed by each participant by age 35. Educational categories range from compulsory primary education to advanced master’s level and doctoral degrees. By integrating these extensive datasets, the researchers mapped out how adolescent assessments and adult education levels mapped to subsequent medical visits for psychological care.
The results demonstrated a steady upward trend in psychological well-being as adolescents’ cognitive scores increased. Men who scored the lowest on the military assessment were about three times more likely to receive a mental health diagnosis than the group who scored the highest. Almost 30% of the lowest scoring group experienced a diagnosable condition in adulthood.
Only 10 percent of the highest-scoring participants sought primary care for mental health issues. When educational performance was factored into the analysis, a clear pattern of vulnerability emerged. Earning a college degree had a protective effect regardless of initial baseline test scores.
Men who recorded lower cognitive scores and completed only compulsory education had the absolute highest rates of experiencing mental illness. Almost 40% of this particular demographic group were diagnosed in midlife. The gap between this highly vulnerable group and the most protected group was large, reaching almost 30 percentage points.
The researchers also evaluated a popular concept known as the superbrain theory, which suggests that unusually high intelligence may predispose individuals to psychological confusion. Previous research among members of high-IQ societies suggested that extreme cognitive abilities are associated with sensitive nervous systems and increased risk of anxiety and depression. Norwegian population data did not support this hypothesis.
Instead of showing increased vulnerability, the men who achieved the absolute highest test scores had the lowest rates of clinical diagnosis for almost every condition studied. The protective effect of high test scores remained strong even at the top of the score distribution.
There was one notable exception to this general pattern across diagnostic categories. The prevalence of affective psychosis, a medical category that includes bipolar disorder, did not closely match performance on cognitive tests. The relationship between adolescent test scores and this particular mental illness was much less pronounced than the dramatic gradients seen for depression and substance abuse.
The researchers wanted to make sure their findings were not just a byproduct of poverty or difficult family backgrounds, which can lower test scores or harm health. To isolate these variables, the research team performed a comparative analysis using data from more than 80,000 siblings. Siblings typically share parents, adolescent households, and general demographic backgrounds.
When looking only at differences between siblings raised under the same roof, the association between lower cognitive scores and increased psychiatric risk remained. However, associations with specific symptoms such as post-traumatic stress disorder and personality disorders were not statistically significant in the sibling model. For most other conditions, within-family analyzes suggested that mental health disparities are truly related to specific individuals’ cognitive trajectories, not just parental income.
The researchers proposed several possible reasons for this lifelong, persistent connection. People with low scores on cognitive tests often end up in lower-paying jobs and have less educational attainment. Admission to this occupation can lead to difficult working conditions, economic instability, and residence in areas with scarce resources.
These environmental stressors can accumulate over decades and place a heavy burden on an individual’s psychological resilience. Living in a modern society where academic and professional accomplishments are highly valued can also cause lasting friction for those who struggle in traditional learning environments. Continued poor performance can lead to chronic stress, which often leads to severe depression and anxiety.
The authors noted that men with low cognitive scores and leaving school early may represent an under-recognized population in need of preventive psychological care. Developing specialized support systems for adolescents who are struggling in academic settings may help reduce the increased risk of future psychiatric emergencies. Better vocational counseling and targeted therapy adaptation may improve outcomes in this group.
Although the study utilized a large national registry, the research team acknowledged some limitations to their approach. This analysis relied only on primary care diagnoses recorded by general practitioners. This means that men who experience deep psychological distress but do not seek formal treatment are completely excluded from the disease count.
If a person with high cognitive abilities happens to deal with emotional stress without seeking medical attention, their avoidance behavior may affect their final health statistics. Furthermore, the study only included Norwegian men born in a particular decade. Norway is characterized by a strong universal healthcare system and a strong social safety net, so the observed patterns may not be directly applicable to countries with different economic realities.
Finally, the researchers cautioned against assuming a strictly unidirectional causal relationship between adolescent test scores and later mental health. Although the psychiatric evaluation was conducted nearly 20 years after the cognitive testing, some participants may have experienced undocumented psychological distress in early childhood. Early psychological distress can interfere with basic academic learning and subsequently cause lower test scores in late adolescence.
The study, “Cognitive ability and educational attainment as antecedents of mental disorders: A male population study,” was authored by Magnus Nordmo, Hans Fredrik Sunde, Thomas H. Kleppestø, Morten Nordmo, Avshalom Caspi, Terrie E. Moffitt, and Fartein Ask Torvik.
