A study recently released by University researchers shows that individual differences in the ways in which a child produces syntax is influenced by the child’s language environment. This study bucks the conventional wisdom that an individual’s language develops uniformly through that person’s inherent characteristics.

The study, which showed that students in language-rich preschool classrooms experience twice the growth in ability to use complex sentences when compared with students whose teachers don’t use complex sentences often, has major implications for all aspects of preschool education.

“We found sizable individual differences among children in the proportion of multi-clause sentences produced as well as comprehending,” said Janellen Huttenlocher, one of the paper’s authors and the William S. Gray Professor in the department of psychology and the College.

“This study provides evidence that input does matter,” explained Marina Vasilyeva, a research associate in the department of psychology and a co-author of the paper. “In this study, we tried to control for income and look for data that supported either nature or nurture.”

The researchers found that children’s comprehension, syntax, and language development are directly related to their parents’ aptitudes in those characteristics, although they could merely be reflecting genetic characteristics. To get around this difficulty, University researchers went into children’s classrooms and recorded the teachers to see what impact their speech had on the children’s speech.

The parents’ language development was assessed with tape recorders in parent-child conversations while the pre-school teachers were observed in their classrooms during the middle of the year.

About 305 children at 17 preschools in and around Chicago participated in the study. They were spread out over a high-income group, a low-income group, and a mixed-income group.

The children were tested on language comprehension at the beginning of the school year and end of the school year.

The children were shown pictures and asked to match the correct picture with a complex sentence such as “The boy is looking for the girl behind a chair, but she is sitting under the table.”

“Children learn in a wide variety of environments,” Vasilyeva said. “There are more-advanced learning environments and then less-sophisticated environments. Yet everyone more or less is able to learn language to the same degree.”

Kristi Schoendube, associate director for outreach at the Center for Early Childhood Research Center, said the $100,000 cost of the research came from a $2 million grant from the McCormick Tribune Foundation.

In the future, tests will monitor children as they progress from 14 months to 58 months.

To ensure the diversity of the setting, class, and gene characteristics, 65 children will be part of the study.

Additionally, to probe the differences between nature and nurture, researchers will assess both the children’s primary caregiver and preschool teachers.

The study, “Language Input and Child Syntax,” was published in the November issue of Cognitive Psychology.