Primary school teacher helping a girl writing at her desk

A landmark study in 1995 revealed that children who come from families with higher incomes are exposed to thirty million additional words in the initial three years of life than children of lower-income families. The “30-million-word gap” correlates with substantial variations in the tests of language, vocabulary development and comprehension of reading.

Cognitive scientists from MIT have discovered that a conversation between an adult and a child is likely to modify the child’s brain and is more important in developing language than the gap between words. A study of children aged between four and six discovered that the differences in the amount of “conversational turns” accounted for significant differences in brain physiology and language abilities that they observed in the children. The findings applied to all children, regardless of parents’ earnings or educational level. The research suggests that parents have a significant influence on their children’s speech and brain development simply by talking to them, the researchers claim.

Utilizing Functional Magnetic Resonance Imaging, the researchers found differences in the brain’s response to language. For children who had more conversation, Broca’s area, a region of the brain responsible for producing speech and language processing, was more active as they listened to stories. The brain’s activity was then correlated with children’s scores on language assessments, which fully explained the differences in income that affect children’s communication abilities.

Beyond The Gap in the Words

Before this study, nothing was known about the “word gap” might translate into brain differences. The MIT team discovered these differences by analyzing images of kids’ brains with diverse socioeconomic backgrounds.

In the study, researchers employed an instrument called Language Environment Analysis (LENA Program) to document every word said or heard by every child. Parents who consented to let their children participate in the experiment were instructed to ensure that their children wore recording devices for two days, from when they woke up until when they went to sleep.

They were examined using a computer program which gave three metrics that included the number of times the child spoke words, the number of words that were spoken to the child, and the number of times the adult and child were able to take the “conversational turn”. Either initiated this exchange.

Researchers discovered that the number of conversations turned per minute was strongly correlated with children’s scores on the standardized tests for proficiency in a language, such as grammar, vocabulary and reasoning in the verbal. Conversational turns were also associated with higher activity in Broca’s space if the children listened to stories inside an fMRI scanner. Researchers believe interactive conversations can give children more opportunities to develop communication skills.

It includes the ability to discern what someone else wants to communicate to respond suitably. Although children from higher-income families had access to more languages on average and children from lower-income families who were exposed to a large number of conversations were proficient in the language. They had Broce’s brain activity was similar to the children from more wealthy families.