Are we getting dumber over time?
As a child, I always thought that intelligence and IQ were inborn. In other words, I thought certain people were A students, B students, and so forth. Not until college did I prove to myself that this was false. Intelligence is a complex mystery of the mind, and no one really understands it. Scientists have made few advances in comprehending it.
I read recently the engaging "Are Humans Getting Smarter or Dumber?" in LiveScience recently, and Stephanie Pappas pushed me to think more deeply. She notes the dramatic rise in IQ over time starting from the point when they began recording the statistics.
Humans growing smarter: Environment
Controversy, I found, surrounds the whole system of examining and comparing intelligence over time, and I was left unsatisfied with the results presented. The reality is that IQ and other measures of intelligence focus simplistically on different mental abilities.
Researchers had groups of people take IQ tests that were designed for past generations. So, participants would take a test from 1930 for example, and researchers compared the results with the historical data. The Flynn effect refers to truth that a person now taking an IQ test designed in the past performs better.The changes are dramatic, with an average improvement of 3 points per decade.
Scholars attribute these changes principally to environmental factors such as schooling quality, opportunity, knowledge of learning, and even nutrition. Modern environments change the way that people respond to questions on IQ tests. So, IQ tests suggest that humans are growing smarter in a richer environment.
Humans growing dumber: Genetics
However, despite the proven growth in IQ, many scholars argue that we are, in fact, growing less intelligent as time passes. A study in 2012 from the Stanford University School of Medicine, published in the journal of Trends in Genetics, argues that human intelligence climaxed about 2,000 to 6,000 years ago.
According to Crabtree, the leader of the study, about 2,000 to 5,000 genes govern human intelligence, and within the past 3,000 years mutations have occured that have had a negative impact on intelligence.
Crabtree suggests that intelligence was far more important to hunting and gathering humans than to us. Back then, ignorance would lead to injury and death, and we do not face such severe consequences.
So, are the impressive IQ results based solely on our environment, with genetics actually proving that we are less intelligent?
Another theory also points to a decline in human intelligence because of dysgenic mating, which basically means that since the 1800's the smartest humans have had the fewest babies. The greater intelligence provided these people with motivation and ability to regulate their birth rate. So, less intelligent people have been reproducing at a greater rate according to this theory.
IQ versus reaction time: Genetics
Woodley claims to have resolved the conflicts. A certain group of scholars in the 1800's placed more emphasis on reaction time than on IQ. They measured how long it took people to solve a problem or respond to a question. These researchers, and Woodley, believe that reaction time is a more accurate measurement of basic cognitive abilities. If a person reacts quickly, she is smarter than one who responds more slowly.
The reaction times measured since the 1880's show that we are slowing down. Woodley claims the results are clear and the timing accurate, suggesting that our overall capacity to become more intelligent is in decline despite the rising IQ. In other words or current scores are inflated because of our stimulus rich environment, but our capacity to increase basic intelligence is in decline genetically.
However, detractors believe reaction time is not the most significant indicator of intelligence. Also, they claim the standards of measurement in the 1880's could not possibly be comparable with those of today. Other flaws in Woodley's analysis raise questions about his findings.
Reframing the issue: Humans, tools, and society
Comparing IQ and reaction time seems problematic. They seem like two completely different qualities, like comparing how fast someone can run to how far another person can jump. Neither seem definitive in measuring human intelligence.
The scholars are looking at pieces of human intelligence and claiming them to be the whole. In fact, each side is examining only a small fraction of what the human mind can do. Neither side is right, or they are both partially correct.
I place human intelligence in a far more complex context, unlike when I was a child:
Let me dramatize this a bit. How smart is a man if you put him in an empty, square room, hungry and thirsty, by himself, with no objects in the room, and with no other person present?
Now give the man some food and water. How smart is he? Put a table and chair in the room. Give him a ruler. Slip a geometry book under the door. Let him use a calculator. Provide him with an iPad and wifi connectivity.
Allow his best friend to enter. His wife. Let a mathematician enter the room with him. Stick in a geek who knows something of computers. And so on.
The intelligence of the man depends on so many variables, and by isolating some of them, you at best get a small glimpse of his mental capacity. True measurement of intelligence involves much more than IQ and speed.
Modern human intelligence lies both inside and outside the mind. This is a powerful idea. Technology and society are extensions of an individual's mind, empowering him or her with "intelligence" surpassing any human from the past. You cannot separate, in a meaningful way, a human being from his tools and culture. Any measure of intelligence must account for multiple intelligences, technology, and society.
Examining reaction time and IQ are interesting, but trivial in the end.
Oh, I forgot, give the poor man some clothes.
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