What is the Flynn effect?

• A. The observed rise in average IQ scores over the 20th century across populations.
• B. A decline in IQ scores due to increased test complexity.
• C. A plateau in IQ scores after early adulthood.
• D. A sudden rise in IQ after short-term training.

Answer: (A)

The Flynn effect is the long-term rise in average IQ scores observed across many populations over the 20th century. This pattern shows generations scoring higher on standardized intelligence tests than earlier generations, even though the tests are periodically re-normed to keep the average around the same point. It’s thought to reflect environmental and societal changes—better nutrition, education, health care, more cognitively demanding daily life, and greater familiarity with test-taking—rather than a sudden boost from short-term training or a fixed increase in innate ability. It doesn’t describe a plateau or a decline, and it isn’t about rapid gains from individual practice.