In 1970, authorities became aware of a child who the world would come to know as "Genie." Genie had spent her life socially isolated, tied in a chair or locked in a cage. At age 13, she had a vocabulary of only about 20 words. Despite numerous attempts by social workers and psychologists, Genie’s verbal communication never fully developed. Her tragic case raised new questions about the importance of the environment in early childhood language acquisition, a topic that researchers continue to study.
Communication and Sentence Structure
A 2002 study by researchers at the University of Chicago revealed that syntax, or sentence structure, is learned rather than innate. Essentially, researchers found that speaking to young children in complete and complex sentences, rather than using “baby talk,” helps them to develop the ability to understand and use complex sentence structures.
Cognitive psychologists already knew that “the degree of complexity in children’s language was directly related to that of their parents,” but had not yet determined whether this was due to a genetic advantage or because of the child’s environment. Researchers studied preschool classrooms to evaluate the effects of teachers’ sentence structure and language use on children. Students of teachers who frequently used complex sentences developed advanced language skills twice as fast those in classrooms where the teacher used simpler language.
The primary caregiver’s vocabulary may be one of the most important indicators of vocabulary development in young children. Further, early vocabulary acquisition is directly related to future academic success. A Florida Atlantic University study found a positive correlation between socioeconomic status and a child’s vocabulary. The study isolated a particular factor, maternal vocabulary, and found that mothers in a high socioeconomic bracket not only had more advanced vocabularies, but also talked to their children using more complex language than mothers in a middle bracket did.
Childcare Setting and Vocabulary
About 75 percent of children have mothers who work outside the home at least part-time. As a result, many children spend a significant portion of their formative years in a childcare setting, such as a daycare center, in-home care facility or in a relative’s care.
A Purdue University study analyzed data from young children in different childcare settings and found that the quantity and quality of childcare directly affected a child’s vocabulary and reading scores throughout early elementary school. Children receiving higher quality care had higher vocabulary scores when tested in kindergarten through fifth grade, particularly when compared to children in a daycare center setting. The amount of time per week spent in childcare also had a negative correlation with later vocabulary test scores.