Our brains shape and reshape themselves in ways that depend on how we use them. Learning a language is a nice example of how experiences contribute to each person’s unique pattern of brain development. The ability to speak and to understand speech requires minimal exposure to a language. However, which language a child learns to speak depends on the language he/she experiences, and their brain will adapt to this specific language. When an infant is 3 months old, their brain can distinguish several hundred different spoken sounds. This is substantially more than are present in any language. Over the next several months, however, the brain will organize itself more efficiently so that it only recognizes those spoken sounds that are part of the language that he/she regularly hears. For example, a one-year-old Japanese baby will not recognize that “la” is different from “ra,” because the former sound is not used in Japanese. During early childhood, the brain retains the ability to re-learn sounds it has discarded, so young children typically learn new languages easily and without an accent. When a child is 10 years or older, plasticity for this function is greatly diminished; therefore, most people find it difficult to learn to speak a foreign language as well as a native speaker if they only begin to learn it in adolescence or adulthood.
More importantly, early experiences can determine how proficient a child becomes in his or her native language. Researchers found that when mothers frequently spoke to their infants, their children learned almost 300 more words by age 2 than did their peers whose mothers rarely spoke to them. Infants need to interact directly with other human beings. They need people to talk to them about what they are seeing and experiencing, for them to develop optimal language skills. Unfortunately, many parents are under the mistaken impression that talking to babies is not very important because they are too young to understand what is being said.
To ensure that disadvantaged children obtain experiences that support optimal development, a new consensus is emerging about the importance of intervening with families in the first months and years of a child’s life. Psychologists have long known that children of poorly educated, low-income parents often don’t reach the same intellectual levels as children of well-educated, wealthy parents. Studies have provided new insights into why this is so. Parents who are preoccupied with a daily struggle to ensure that their children have enough to eat and are safe from harm may not have the resources, information, or time they need to provide the stimulating experiences that foster optimal brain development. Infants and children who are rarely spoken to, who are exposed to few toys, and who have little opportunity to explore and experiment with their environment may fail to fully develop the neural connections and pathways that facilitate later learning. Despite their normal genetic endowment, these children are at a significant intellectual disadvantage. Fortunately, intervention programs that start working with children and their families at birth or even prenatally can help prevent this.
Source: “The Power of Early Experiences,” from Starting Smart: How Early Experiences Affect Brain Development, by Theresa Hawley. Ph.D.