Intelligence in children: Can we make our kids smarter?

© 2008 Gwen Dewar, Ph.D., all rights reserved

Intelligence-boosting products are big business: Books, toys, DVDs, software, games, and educational programs designed to make your child into an intellectual prodigy.Many of these products come with claims—-explicit or implicit—-that their usefulness is supported by scientific evidence.
Are they really?
Sometimes. For instance, scientific studies suggest that

• playing with blocks may help kids develop a variety of cognitive skills

• music training raises a child's IQ

• academic programs that teach critical thinking skills enhance IQ

• some board games boost preschool math skills

• some video games enhance spatial skills and working memory

But many “brainy” products are snake oil—-or just downright silly. Like the DVD that presents babies with images of toys while a series of disembodied voices recite nursery rhymes in English, French, German, Hebrew, Japanese, Russian and Spanish.
I’m not sure what this experience is supposed to achieve, but it’s not going to teach babies language. Research indicates that babies learn language by listening to, interacting with, and following the gaze of live human beings—-not talking televisions (Kuhl 2005).
Then there are misconceptions and folk beliefs—-like the idea that praising kids for their intelligence will raise self-esteem and improve their academic performance.
An impressive series of experiments suggests that the opposite is true.Praising kids for being smart tends to make them act dumb.

Even more interesting--at least to me--is the discovery that what you and your kids believe about intelligence can hamper the learning process.
People who believe that intelligence is a fixed, unchanging trait are less likely to learn from their mistakes and less likely to succeed in school.

Moreover, experiments suggest that your child's awareness of social stereotypes about intelligence and achievement (e.g., "girls have stronger language skills," or "Asian kids are math prodigies") can undermine his academic performance.

So here I present my guide to the “good bets”—evidence-based information about the ways that parents can nurture their children’s intelligence. If you don’t see a topic of interest, let me know. And check back later—-I will be adding more articles over time.

Breastfeeding and IQ

Breastfeeding boosts a child’s IQ by about 7 points-—if, like 90% of the population, he carries the FADS2 gene (Caspi et al 2007).FADS2 controls the metabolism of fatty acids, and researchers suspect that that breast milk enhances IQ because it contains long-chain polyunsaturated fatty acids (DHA and AA) required for neurons to communicate effectively.

Exercise and intelligence

It’s both intriguing and unexpected: Aerobic exercise stimulates brain growth and enhances our ability to learn. Studies also suggest that exercise helps kids focus attention in school. But there’s a catch: exercise must be voluntary. Animal studies suggest that involuntary exercise doesn’t yield the same benefits.Click here for the whole story.

The cognitive benefits of play

Free play promotes better learning, memory, and growth of the cerebral cortex. It also enhances the development of language, spatial intelligence and mathematical skills. For more information, see this article on the cognitive benefits of play.

Working memory: The new IQ?

New research indicates that working memory capacity--that mental notepad that we use to think thoughts and solve problems--is a better predictor of school achievement than IQ. Read more about working memory and the evidence that you can improve your child's working memory skills with training. .
Hand gestures free up working memory and help kids learn
And here's an unlikely bit of news: It turns out gesturing with your hands improves your ability to remember and learn.
Cognitive psychologist Susan Goldin-Meadow and her colleagues have conducted a series of experiments showing that kids are more likely to remember words, events, and even math lessons when they gesture with their hands.
For the details, see this article on the science of gestures.

Secure attachments and intelligence

Researchers have noted a correlation between child IQ scores and attachment status. For instance, one study of 36 middle-class mothers and their three-year-olds found that securely-attached children scored 12 points higher on the Stanford-Binet intelligence test than did insecurely attached children (Crandell and Hobson 1999).What’s responsible for this correlation? It’s possible that more intelligent children have an easier time forming secure attachments. For instance, more intelligent kids are probably better at interpreting their parents’ behavior and selecting the most appropriate response (Waters and Valenzuela 1999).
But there is also experimental evidence suggesting that responsive parenting—which promotes secure attachments—contributes to higher IQ.
In these experiments, some mothers were randomly assigned to receive training in responsive parenting techniques. The infants of trained mothers showed greater growth in cognitive skills than did the infants of control moms (Landry et al 2003; 2006).

Mindsets for failure: Beliefs that hold your child back

Does your child believe that intelligence is a fixed trait?

Fascinating experiments indicate that what we believe about intelligence can impede our ability to learn.People who believe that intelligence is a fixed, stable trait are more likely to avoid challenges. They are also less likely to learn from their mistakes--and the difference shows up in bran scans. Read more about this phenomenon and how it affects kids.

Does your child believe that “people like me” don’t do well academically?

If so, her beliefs might be undermining her performance in school. Sound like politically correct propaganda? There is actually a lot of solid experimental evidence confirming the existence of “stereotype threat.”Learn more about this research and what you can do to counteract its effects.

How praise can undermine your child’s capacity to learn

Praise can be a great motivator. But it can also make kids focus on the wrong goals. Research shows that the wrong kinds of praise can actually undermine motivation and leave kids feeling helpless when they fail. For more information, see this article about the perils of praising kids for being smart.

Sleep and intelligence

Sleep and learningThere is a convincing body of evidence to suggest that we are more likely to retain what we’ve learned—-and more likely to achieve new insights—if we go to sleep shortly after our studies (Gais et al 2006; Wagner et al 2004).
People don’t need to sleep all night for the effect to work. Naps as short as 60 minutes are as effective—-as long as sleepers experience both REM and slow-wave, “deep” sleep (Mednick et al 2003).
The effect has been demonstrated on kids as well as adults (Backhaus et al 2008). So it seems to make sense for kids to schedule their studies before naps and bedtime. Unfortunately, institutionalized learning doesn’t make room for study-naps! It would appear that home-schoolers-—and other kids with flexible academic schedules—-are at a distinct advantage.
Sleep and cognitive development
It’s also possible that chronic sleep restriction has a more lasting effect on cognitive performance.
In a study tracking Canadian kids from age 2.5 to 6 years, researchers found that kids who were poor sleepers as toddlers performed more poorly on neurodevelopmental tests when they were 6 years old (Touchette et al 2007).
This was true even for kids whose sleep improved after age 3. The researchers speculate that there may be a “critical period” in early childhood, when the effects of sleep restriction are especially harmful (Touchette et al 2007).

Math, logic, and critical thinking

Stanislaus Dehaene is a cognitive scientist and expert on the mathematical brain.He argues that many kids have poor math skills because they are discouraged from developing an intuitive sense of number.
For more information, check out this article about the"number sense."

In addition, see this article about the way that some board games can help preschoolers develop their math skills.

And what about logic? Experimental studies suggest that explicit instruction in critical thinking--including lessons in basic logic, hypothesis testing, and scientific reasoning--can raise a child's IQ.

Unfortunately, such lessons are not yet a common part of most high school--let alone middle school curricula. Even worse, I suspect that the media and other influences are training our kids to think with blinders on. To see what I mean, read this article on critical thinking in children.

Music and intelligence

The “Mozart Effect” hasn’t been totally discredited. However, it’s perhaps better labeled the “pleasurable experience effect.” That's because just about any kind of music—-or relaxing form of entertainment—-may temporarily boost certain types of cognitive performance. Listening to music might also stimulate a temporary boost in creativity. For more information, check out this article on the Mozart effect.

The Mozart effect is about merely listening to music. But what about making music?It turns out that music training reshapes the brain. It may even raise the IQ. Read more about music training and intelligence.

Free choice

Kids show greater motivation and perform better when they get to choose what they do (Iyengar and Lepper 1999).Well—that’s true for some American kids, anyway. It turns out that the effect is culture-specific. One study compared Anglo-American and Asian American kids. While the Anglo-Americans preferred tasks they had chosen for themselves, the Asian Americans showed more motivation when their choices were made for them by trusted authority figures or peers (Iyengar and Lepper 1999).
The upshot? There may be no “one size fits all” approach to classroom learning. Some kids may thrive when teachers give them choices. Others might find this approach to be disconcerting.

Toys that boost cognitive skills

Although there is evidence that action video games improve spatial skills (see below), some of the most important developmental toys are the most old-fashioned—-toys that permit kids to exercise their creativity and to explore cause-and-effect relations in the physical world.For instance, toy blocks may be among the best developmental toys around. Research suggests that block play enhances spatial skills, math skills, problem-solving ability, and verbal skills.

Video game playing can enhance spatial skills

Spatial skills are important for math and engineering, and males tend to do better than females on spatial tasks.But research suggests that people of both sexes can improve their spatial skills by playing action-oriented video games.
In one recent experiment, people were assigned to play either an action video game or a non-action, control video game.
After folks had accumulated 10 hours of practice time, those who played the action video game substantially improved their spatial attention and their capacity for spatial rotation--i.e., rotating three dimensional shapes in the mind's eye. Both males and females benefited, but females made greater gains (Feng et al 2007).
Other experiments show that people can improve their ability to count moving objects by playing action video games (Green and Bavelier 2006).Too much of a good thing?
This news will no doubt delight the avid gamers in your household. But there is a (rather obvious) downside to gaming: Kids who play video games tend to spend less time doing other activities. In one survey of American kids aged 10-19, those who played video games spent 30% less time reading and 34% less time doing homework. So it appears that, like most things, video games are best used in moderation.

References: Nurturing intelligence and promoting achievement in kids

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