In a study, researcher James Flynn examined IQ test scores from many countries across the 20th century. After standardizing tests so that the average score was always 100, he discovered that raw scores on tests like the Raven's Progressive Matrices had risen by roughly 3 points per decade. This rise meant that someone who scored "average" by 1930 norms would score below average by today's norms.
Which explanation for the Flynn effect is most consistent with current research?
- Acheck_circle
Improved nutrition, education, and exposure to abstract reasoning have raised performance over generations.
- B
The human gene pool has rapidly evolved higher intelligence in 70 years.
- C
IQ tests have systematically gotten easier each decade.
- D
People are guessing better on multiple-choice items each decade.
Explanation
Most researchers attribute the Flynn effect to environmental factors such as improved nutrition, schooling, smaller family size, and growing familiarity with abstract problem solving. Genetic evolution does not occur on this short timescale.