Elsevier

Intelligence

Volume 49, March–April 2015, Pages 144-158
Intelligence

The cognitive impact of the education revolution: A possible cause of the Flynn Effect on population IQ

https://doi.org/10.1016/j.intell.2015.01.003Get rights and content

Highlights

  • Is growing exposure to formal education over the 20th century a cause of the Flynn Effect?

  • Study 1 examined academic numeracy tasks and prefrontal cortex activation among 8–19 year-olds.

  • Study 2 examined variable exposure to schooling and cognitive executive functioning among subsistence-level farmers.

  • Study 3 examined the cognitive demand of primary school mathematics textbooks over the 20th century.

  • Findings suggest that mass education is one cause of the Flynn Effect.

Abstract

The phenomenon of rising IQ scores in high-income nations over the 20th century, known as the Flynn Effect, indicates historical increase in mental abilities related to planning, organization, working memory, integration of experience, spatial reasoning, unique problem-solving, and skills for goal-directed behaviors. Given prior research on the impact of formal education on IQ, a three-tiered hypothesis positing that schooling, and its expansion and intensification over the education revolution, is one likely cause of the Flynn Effect is tested in three studies. First, a neuroimaging experiment with children finds that neuromaturation is shaped by common activities in school, such as numeracy, and share a common neural substrate with fluid IQ abilities. Second, a field study with adults from insolated agrarian communities finds that variable exposure to schooling is associated with related variation in the mental abilities. Third, a historical–institutional analysis of the cognitive requirements of American mathematics curriculum finds a growing cognitive demand for birth cohorts from later in the 20th century. These findings suggest a consilience of evidence about the impact of mass education on the Flynn Effect and are discussed in light of the g-factor paradigm, cognition, and the Bell Curve debate.

Section snippets

Rising population cognitive performance and exposure to education

Mean IQ test scores of cohorts of American adults increased by approximately 25 points over the last 90 years, a period during which successive cohorts of children and youth were exposed to more formal education as shown in Fig. 1. For Japan, South Korea, and nations of Western Europe, where there is a history of large-scale IQ testing, similar Flynn Effects and increases in educational attainment have been reported (Flynn, 1984, Flynn, 1987, Lynn, 2009a, Lynn and Meisenberg, 2010, te Nijenhuis

Study 1. Neuroimaging experiment: conjoint fMRI analysis of CEFs and calculation schooling tasks

Establishing schooling-related activation of the neural substrate involved in CEF performance is a necessary first step to test H1 and satisfy causal condition 1. Functional magnetic resonance imaging (fMRI) and analysis of its blood oxygenation level dependent (BOLD) changes yield data about regional brain activation during performance of specific tasks. The ontogenetic-causal logic behind fMRI evidence is supported by a large set of empirical findings concluding that the neurodevelopment of

Discussion

Overall, the neurological, cognitive, and textbook-analysis results support the three-part schooling-cognition enhancement hypothesis, and for each set of findings there is supplemental corroborating evidence from related research.

The findings from Study 1 provide neurological evidence for H1 as brain activations associated with mathematical problem solving shared a common neural substrate with relational reasoning and other CEF capacities during the developmental years of schooling. These

Implications of the schooling-cognitive enhancement hypothesis

If future research supports the current findings that the education revolution is one cause of rising population IQ over the past century, there are several major implications. Emerging conclusions from the study of human genetics and the ontogenesis of neuro-cognition indicate that neurological and cognitive development occurs through activity-dependent neural plasticity (e.g., Quartz & Sejnowski, 1997). In other words, inheritance of genetic potential for intelligence and relevant

Acknowledgments

The authors acknowledge funding from the National Science Foundation (SES-0826712; SES-1155924).

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