It is often said that as we get older, we become less mentally capable; however, is this really the case – do our IQs decrease as we get older?
How fast does intelligence increase if it has it? Do intelligence declines differ based on different types of intelligence?
‘ Does IQ decrease with age ?’ five experts in intelligence, behavior sciences and psychology posed the question to Metafact. Here’s what they said…
What is IQ and how is it measured?
” intelligence is usually assessed through measures such as language skills tests, which may also evaluate your verbal and nonverbal abilities, or your ability to finish tasks quickly”, says Michael Thomas, an expert in psychology and neuroscience from Birkhbeck University in England.
“Match the score of other people versus the score you will achieve on these challenges.”
How well you retain and comprehend information, your visual-spatial processing, and your abstract reasoning are all components of your IQ score.
‘Intelligence quotient’ is a standardized score based on your age that represents your intelligence.
At 100 points on the IQ scale, your intelligence would be 100, and below 100 it would be zero.
How does an individual’s IQ change with age?
The intelligence of an individual does not change.
The score you get on an IQ test is always based on how well you do compared to other people of the same age. Therefore, if you took an IQ test now, you would probably get the same score as when you were 25.
“The amount of information a person understands relative to his or her age is always calculated, irrespective of the age.” According to Alan Kaufman, a professor of intelligence testing at Yale University in the United States, “25-year-olds are compared to other 25-year-olds in terms of their performance on specific tasks, just as 50-year-olds are compared to other 50-year-olds.”
“The average or mean IQ for adult age groups is set at 100. Because every group averages 100, we cannot directly compare the mean IQs across the adult age range.”
Meiran Nachshon, a psychologist from Ben-Gurion University in Israel, agrees, saying:
“An individual’s position in the population is very stable relative to the average. ”
He notes that a study found that the IQ of people aged ~11 at the time of their 11th birthday was related to their 90th birthday IQ scores.
How does the average IQ of the population change with age?
To compare the IQ of older people to young people, we need to be able to measure IQ change over time.
An alternative approach is employed when this is not possible.
The solution is explained in the following way:
“We need to come up with a ‘yardstick’ that we can compare adults against. We can use 70-year-olds, 60-year-olds, 50-year-olds, 40-year-olds, and so on as benchmarks.
“We believe that the average IQ of young adults is around age 30 (usually aged 25-34). In that way, young adults have an average IQ of 100 because that is how the norms are constructed. When we compare adults across the lifespan to young adults, we can learn how IQ changes as we grow older.”
“A clear decline in IQ is evident when these tests are done.” According to Kaufman, these tests reveal that IQ decreases significantly.
Not all types of intelligence decline at the same rate
A number of intelligence dimensions are measured by IQ tests.
“Global IQ is made up of fluid intelligence, which is commonly studied, as well as crystallized intelligence, which is included in the mix, along with abilities called working memory and processing speed. Global IQ, in other words, is comprised of all kinds of intelligence.”
“Dealing with fluid intelligence or fluid reasoning is similar to learning and problem solving that aren’t taught in school, whereas acquiring crystallized intelligence or crystallized knowledge measures and learning that are related to schooling and acculturation,” he says.
As you get older, these different types of intelligence display distinct patterns.
“At ages 20-24, crystallized intelligence averages 98, rises to 101 between 35-44, before declining to 100 (65-69), then 98 (70-74), and then 93 (75+),” says Kaufman.
A fluid intelligence peak occurs at age 20-24 (100) and drops gradually to 99 (25-34) and 96 (35-44) before becoming “a rollercoaster plunge to 91 (45-54), 86 (55-64), 83 (65-69), 79 (70-74), and 72 (75+”).
Your knowledge of words will dramatically increase as you age, but your fastest response times will still be available, says Thomas.
“Most cognitive skills rely on things you have learned (so-called crystalized knowledge) in your late sixties, so that your speed decline is more significant. Your cognitive skills may increase or remain stable.”
