Average iq for every age
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Average IQ Across Different Ages: A Comprehensive Overview
Early Childhood IQ Trends
Research indicates that intelligence in early childhood shows moderate stability. A longitudinal study assessing intellectual development from preschool to early adulthood found that IQ stability is higher for shorter intervals between measurement points and increases with age. This suggests that while early childhood IQ can be a predictor of future intelligence, it is not entirely fixed and can change over time.
IQ Differences in Childhood and Adolescence
Studies have shown that there are slight differences in average IQ between genders during childhood and adolescence. For instance, girls tend to have a slight IQ advantage over boys at ages 7 and 11, with an average difference of about 1 IQ point. However, by the age of 16, this trend reverses, and boys exhibit a slight IQ advantage of approximately 1.8 IQ points. This shift highlights the dynamic nature of intellectual development during these formative years.
The Wilson Effect: Increasing Heritability of IQ with Age
The heritability of IQ, known as the Wilson Effect, increases with age. Research shows that the heritability of IQ reaches an asymptote of about 0.80 at ages 18-20 and remains at that level into adulthood. This indicates that genetic factors play a more significant role in determining IQ as individuals grow older, while the influence of shared environmental factors decreases to about 0.10 by the same age.
The Flynn Effect and Its Variability
The Flynn Effect, which describes generational increases in IQ, does not apply uniformly across all ages and ability levels. A study involving 10,000 US adolescents found that while there was an overall increase in IQ scores, the effect varied significantly by age and ability level. For example, IQs increased by 2.3 points at age 13 but decreased by 1.6 points at age 18. Additionally, those with lower IQs (<70) experienced a decrease of 4.9 points, whereas those with higher IQs (>130) saw an increase of 3.5 points. These findings suggest that the Flynn Effect is more complex than previously thought and is influenced by various factors including age and cognitive ability.
Conclusion
In summary, the average IQ varies across different ages, with notable differences observed during childhood and adolescence. The stability of IQ increases with age, and genetic factors become more influential in determining IQ as individuals grow older. Additionally, the Flynn Effect shows that generational IQ changes are not uniform and can vary significantly based on age and ability level. Understanding these trends is crucial for educators, psychologists, and policymakers aiming to support intellectual development across the lifespan.
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