What Is The 30 Million Word Gap?

The Rosetta Stone

Back in the 1960's, Ph.D students Betty Hart and Todd Risley were trying to prove the concept of Tabula Rasa using two different sets of preschool children.  One set had parents who worked at the University of Kansas, and one set were from a place called Juniper Gardens which was a housing project.

Their plan was to show that children learned at the same rate no matter their race or economic status, and if you gave them the same information, they would process it the same way.

Hart and Risley were amazed to discover that they were incorrect.  The four year olds from Juniper Gardens did not process language like the kids from the university.

The university kids were able to assimilate the new words given to them, and they used that language amongst themselves.

The kids from the housing project learned the new language at first, but over time, most were unable to recall the words they'd learned, and they did not routinely use them when speaking to each other.  They also began to loose the ability to even grasp the new language that was being presented to them.

Hart and Risley were able to alter their approach with the kids from Juniper Gardens to increase their ability to learn new language, but it was much harder than what they experienced with the university kids.

They came to a startling discovery.

Whatever mechanism it is that controls how human beings process and learn language must be forming long before the age of four.  They'd started their tests too late in the developmental stage.

This made them want to know how children acquired language before the age of four, and what mechanisms decided how they processed it.

They set up a long term experiment.  Basically, they identified a number of families across the economic spectrum.  These families had to have very specific parameters.  Over the course of the experiment, researchers recorded the amount and quality of speech each family used with their children.

Understand that these families volunteered to be part of this study, so there is a good chance they were not the most neglectful of parents.  Most were working hard to be the most attentive parents they knew how to be.

After years of observation, Hart and Risley took all of the raw data collected and started crunching it into a format that would help them evaluate what they observed.

Some outcomes were obvious.  The children in these households were being groomed to grow up just like their parents.  They were being spoken to in a way that reflected the highest amount of education their parents received.  They were being instructed in values that were appropriate for the lives they were being raised to live.  They were learning the finer points of social interaction in their communities.  They were learning what to value.

The surprise came when they looked at their exposure to language.

Hart and Risley discovered that overall, children from socioeconomically disadvantaged homes heard, on average, 30 million fewer utterances of language than their middle or upper class counterparts by the age of three.

30 Million Fewer Uses Of Language.

They called this disparity the 30 million word gap.


The details of the study and the in-depth results can be found in Meaningful Differences in the Everyday Experience of Young American Children.

In my next post about this subject, I will get into why this gap causes so much trouble and the long term problems that are associated with it.

Happy Researching!