For the longest time, we couldn't figure out the words coming from our nine-month-old son Josh.
Whenever he took a car ride, he would start saying the word "dah," repeating it over and over again as we strapped him into his car seat, "Dah dah dah, goo, dah dah, big-dah, big-dah." It often sounded like a child's version of an old Police song. We couldn't decode it and would just respond, a bit sheepishly, "Dah?" He would emphatically reply, "Dah." Sometimes our response made him happy. Sometimes it didn't do anything at all.
It wasn't until we were tooling down the interstate one fine, sunny day, moon-roof wide open to the clouds, that we finally figured it out.
Josh saw an airplane flying overhead and shouted excitedly, "Sky-dah! Sky-dah!" My wife suddenly understood. "I think he means airplane!" she said. She asked him, pointing to the sky, "Sky-dah?" Josh cheerily replied, "Sky-dah!" Just then a big noisy semi-truck passed us, and Josh pointed to it with concern. "Big-dah, Big-dah," he said. My wife pointed at the truck too, now shrinking in the distance. "Big-dah?" she asked, and he responded excitedly, "Big-dah!" Then "dah, dah, dah."
We got it. For whatever reason, "dah" had become Joshua's word for "vehicle." Later, Josh and I watched a ship cross Puget Sound. I pointed to the container vessel and guessed, "Water-dah?" He sat up, staring at me like I was from Mars. "Wet-dah," he declared, like a mildly impatient professor addressing a slow student.
Few interactions with children are as much fun as learning to speak their language. As they learn to speak ours, heaping tablespoons of words into their minds is one of the healthiest things parents can do for their brains.
Speak to your children as often as you can. It is one of the most well-established findings in all of the developmental literature -- which is why it is among those detailed in my new book, "Brain Rules for Baby: How to Raise a Smart and Happy Child From Zero to Five."
The linkage between words and smarts was discovered through some pretty invasive research. In one study, investigators descended upon a family's home every month for three years and jotted down every aspect of verbal communication parents gave their children. They measured size of vocabulary, diversity and growth rate of vocabulary, frequency of verbal interaction, and the emotional content of the speech. Just before the visits were finished, the researchers gave IQ tests. They did this with more than 40 families, then followed up years later.
Through exhaustive analysis of this amazingly tough work, two very clear findings emerged:
1) The variety and number of words matter.
The more parents talk to their children, even in the earliest moments of life, the better their kids' linguistic abilities become and the faster that improvement is achieved. The gold standard is 2,100 words per hour. The variety of the words spoken (nouns, verbs, and adjectives used, along with the length and complexity of phrases and sentences) is nearly as important as the number of words spoken. So is the amount of positive feedback.
You can reinforce language skills through interaction: looking at your infant; imitating his vocalizations, laughter and facial expressions; rewarding her language attempts with heightened attention.
Children whose parents talked positively, richly and regularly to them knew twice as many words as kids whose parents talked to them the least. When these kids entered the school system, their reading, spelling and writing abilities soared above those of children in less verbal households. Even though babies don't respond like adults, they are listening, and it is good for them.
2) Talking increases IQ.
Talking to children early in life raises their IQs, too, even after controlling for important variables such as income. By age three, kids who were talked to regularly by their parents (called the talkative group) had IQ scores 1.5 times higher than those kids whose parents talked to them the least (called the taciturn group). This increase in IQ is thought to be responsible for the talkative group's uptick in grades.
It takes a real live person to benefit your baby's brain, so get ready to exercise your vocal cords. Not the portable DVD players, not your television's surround sound, but your vocal cords.
What should you say and how should you say it? Find out in these videos:
John Medina is a developmental molecular biologist and author of the New York Times bestseller "Brain Rules." His latest book is "Brain Rules for Baby: How to Raise a Smart and Happy Child from Zero to Five." He is an affiliate Professor of Bioengineering at the University of Washington School of Medicine. He is also the director of the Brain Center for Applied Learning Research at Seattle Pacific University.