In 1995, the now famous Hart/Risley study was published on the impact of language on young children, revealing that  low-income children are exposed to 30 million fewer words than their higher-income peers before age 3. The study, and others that followed, found connections between poor early literacy skills and lifelong academic, social and income disparities, leading to a number of initiatives to help low-income parents understand the importance of language.

Here is an article adapted from the recently published book “Thirty Million Words: Building A Child’s Brain.” The book, by Dana Suskind, is an extension of the research program she founded and directs at the University of Chicago called the Thirty Million Words® Initiative, which is dedicated to helping close the achievement gap by helping parents improve their home language environmentthrough the power of parent language. Suskind is also a professor of surgery at the university as well as director of the Pediatric Cochlear Implant Program.


The Thirty Million Words® Initiative is supported by a coalition of public and private partnerships and is an extension of Suskind’s Project ASPIRE, which she created to assure that her patients from disadvantaged backgrounds reached their full listening and spoken language potentials.


By Dana Suskind

Parent talk in the first three years of life is the power propelling our brains to develop to their optimum potentials. The process is so simple and hidden that you aren’t even aware it’s happening. But in those first three years, when 85 percent of our physical brain growth occurs, parent talk is the brain’s essential nutrition. At no other time in life will brain growth be as robust or influential.

What happens, then, when the language is not there? Researchers Betty Hart and Todd Risely were the first to show that a diminished early language environment predicted a lack of school readiness and ultimate poor academic performance. The phrase “30 million word gap,” referring to the differences they found in the amount of words heard by some children versus others in the first three years has become a part of the early language vernacular. It’s very important to recognize, however, that the term “30 million word gap” is simply a metaphor, relating not just to quantity of words but to quality, as well. Hart and Risley’s research found that children who heard less words also heard harsher, more prohibitive speech, less complex vocabulary, and less conversational give-and-take. In the end, the 30 million word gap is a window into the parent-child relationship.

[The famous ‘word gap’ doesn’t only affects kids. It affects many educators too.]

Why is the effect of parent talk so profound? Because its results are not only predictive of academic success in general, but on reaching potentials in math, spatial reasoning, and literacy, the ability to self-regulate behavior, reaction to stress, and even perseverance.

Let’s investigate on a strength-by-strength basis.

Words and Math

The differences in children’s math ability are already evident in preschool. And those differences are shown to be related to “math talk,” that is the number of math-related words a child has heard. In a study of children from 4 to 30 months, the differences in math-related words heard in a day varied from 4 to more than 250. That translates into a week’s difference of 28 words versus 1,799. Or … even more compelling … a year’s difference of 1,500 math words compared to almost 100,000.

Can words actually make a difference in a child’s math ability? Without question.

In a follow up of the above study, the children, now 4 years old, were shown two cards, each with a different number of dots. The children were told a number then asked to point to the card with that number of dots on it. Those children who had received more math talk were predictably more likely to choose the cards with the corresponding number of dots.

This showed their superior understanding of the “cardinal principle” of mathematics, essential to learning higher math, and corroborated the power of parent talk in providing the foundation for math skills.

Words and Spatial Ability

Spatial ability refers to understanding how things relate to each other physically. For example, the distance of the sun to the earth, the way a puzzle piece fits into another puzzle piece to help form a picture, the difference between the ground floor of the Empire State Building and the 102nd. Spatial ability, an important predictor of achievement in science, technology, engineering, and mathematics, also appears grounded in parent talk.

Researchers in one study analyzed parents’ use of words indicating sizes and shapes of objects, for example, circle, square, triangle, larger, round, pointed, tall, short, etc., to see whether use of these words affected a child’s understanding of the spatial relationships between objects.

The results were impressive. The range of words heard by the children was as few as 5 to more than 525. The range of spatial words spoken by the children had an incredible range of 4 to about 200. Children who heard more spatial words were, it’s not surprising, those more likely to speak, and understand, more spatial words.

The results were reinforced two years later when the children were 4 ½ years old. This time the researchers looked at spatial skills, including how well the children could mentally rotate objects, copy block designs, and understand spatial analogies.

Again, children who had heard and used more spatial words performed much better on the spatial tests. Careful analysis showed that this was not because of being “smarter,” but that it was entirely related to the amount of “spatial talk” in their first years.

What’s most impressive is that a concrete, nonverbal ability can develop as a result of words. This is another example of the incredible power of the brain to translate words beyond the ideas they communicate into broader and more complex applications and abilities.

Words and Perseverance

We can add, we can punctuate, we can figure out where we are in the universe. Where do we go now? And how much effort are we willing to put into getting there? Who would have thought that the best way to help our toddler achieve is to forget about using the word “smart.” “Smart,” without hard work, it turns out, is an unopened gift.   And science corroborates this. Children who heard more praise for their perseverance and tenacity were ultimately better at achieving, even in the face of challenges.

One study compared the effects of praising a child for “smartness” versus for effort. It found that children who had received a higher proportion of “process-based” praise, that is, praise for effort, in their first three years were much more likely at seven to eight years of age to believe in the power of their hard work for achieving goals. Even more compelling, the study found that this mindset predicted math and reading achievement from second to fourth grades.

Words and Self-Regulation

Self-regulation, allows us to solve problems constructively, rather than spontaneously reacting in ways that would exacerbate them. Without self-regulation, intelligence is an almost meaningless gift.

A central factor in a child’s ultimate ability to control behavioral impulses and emotional responses is parent-caregiver language, including how words are spoken. Emerging research tells us that this actually begins before a baby understands language, per se. Just hearing the natural sequence of sounds, it turns out, puts a baby on the path to self-regulation and executive function. Interestingly, bilinguality may be an enhancing factor. Researchers believe that because the bilingual brain is always ready to be active in both languages, it is continuously monitoring for the appropriate response to input. A definite advantage for those with two “native” languages.

Words, Empathy and Morality

We want our children to be good, not in the “obedient” sense, but in the sense of understanding others with empathy and generosity. Reading about the positive effects of “process-based praise” on achievement may make this sentence — “I liked the way you helped your friend with the game” — seem the way to go. Well, in this case, the carefully collected evidence says no. While helping a child develop persistence in solving problems is achieved by praising behavior, helping a child develop a sense of empathy and kindness is best achieved by praising the individual.

In a study of children who were praised either as individuals or for their behavior, children who had been praised as individuals were, when presented with the opportunity for generosity several weeks later, more likely to be generous.

Another study corroborated this. Children from three to six years of age who were asked to be “helpers” were far more likely to help researchers clean up a mess than children who were asked simply to “help.” In fact, the children who heard only, “Would you please help?” were no more likely to stop playing and help than children who had heard nothing.

Who knew that a subtle word difference, a verb versus a noun, could change the response of a child in helping with a chore? Why is this true? Probably nouns are like mirrors, showing us who we are. And most of us, it turns out, want to look in that mirror and see “good!”

The Final Word:

All children deserve the ability to reach their potentials. While traditional thought has said this begins on the first day of school, science tells us something very different. It says that if we want our nation’s children to be all they can be, intellectually, productively, creatively, we must begin to recognize that ultimate achievement begins on the first day of life and that parents must be recognized as the critical factor. Without that becoming part of our country’s narrative, without well-designed programs to give support to parents who want and need it, we are wasting more than the lives of our children.  As we’ve described in our book “Thirty Million Words,” making sure all our children, no matter the circumstances of their birth, reach their potentials in life, intellectually and emotionally, has far greater ramifications than simply the child; ultimately it is our nation’s future.

As the saying goes, when you save one child, you save a world.

And that, in a word, is what it’s all about.