New research from Northwestern University in Illinois finds that American’s IQs are dropping. IQ — a term that stands for Intelligence Quotient — has been used for decades as a standard measure of problem-solving ability, intelligence, and logic and reasoning skills. From 1932 until 2012, IQ scores increased as much as five points per decade, a phenomenon known as the “Flynn Effect.”
However, researchers from Northwestern University have discovered a “reverse Flynn Effect” going back all the way to 2006. Study author Elizabeth Dworak and her team examined data from almost 400,000 people who had taken an online personality assessment called the Synthetic Aperture Personality Assessment (SAPA) Project. The test provides users with insight into 27 different personality traits, and there are also sections that measure cognitive ability.
The researchers found that scores associated with “verbal reasoning (logic, vocabulary), matrix reasoning (visual problem solving, analogies), and letter and number series (computational/mathematical)” all declined from 2006 to 2018, while scores for 3D rotation or spatial reasoning increased. These changes were consistent regardless of education level, age, or gender.
So, are we really all getting less smart? Not so fast. Dworak stressed that the decline in scores doesn’t necessarily mean Americans aren’t as intelligent as their grandparents or great-grandparents were.
“It doesn’t mean their mental ability is lower or higher; it’s just a difference in scores that are favoring older or newer samples,” she said in a press release. “It could just be that they’re getting worse at taking tests or specifically worse at taking these kinds of tests.”
Dworak also said there are numerous possibilities for the decline, ranging from poor nutrition to a rise in screens and media consumption to pollution and a decline in overall health.
“If you’re thinking about what society cares about and what it’s emphasizing and reinforcing every day, there’s a possibility of that being reflected in performance on an ability test,” Dworak said, citing the increased emphasis on STEM education over the last ten years.
Dworak also noted that since the SAPA project was advertised as a personality test, users could have been less motivated to answer questions that did not directly relate to personality, resulting in lower scores for sections dealing with aptitude.
IQ measurement has a controversial history. Many scholars and researchers believe that IQ tests don’t give an accurate picture of what we refer to as intelligence. There are also questions as to the validity of IQ testing across disciplines — IQ tests tend to measure academic aptitude at the expense of social and emotional intelligence and artistic creativity. And there are strong historical ties between IQ tests and the eugenics movement.
Still, though, there is room for more research to determine what caused the relatively abrupt change in Americans’ IQ in recent years. “There’s debate about what’s causing it, but not every domain is going down; one of them is going up,” Dworak said. “If all the scores were going in the same direction, you could make a nice little narrative about it, but that’s not the case. We need to do more to dig into it.”
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