A new study has found that by age 3, environmental influences such as parenting are relevant factors in the development of toddlers’ self-control when they are asked not to do something they want to do, such as eat a forbidden snack.
“Understanding the development of self-control mechanisms is vital as individuals with low levels of inhibitory control develop more cognitive and socioemotional development issues, including attention-deficit hyperactivity disorder or ADHD,” said Dr. Jeffrey Gagne, an assistant professor of psychology at the University of Texas at Arlington and co-author of the study.
“Currently, most developmental issues are diagnosed after the child enters school,” he continued. “If we could identify and intervene with problems earlier, we could improve their responses before they reach school and their outcomes once they get there and beyond, even through adolescence.”
For the study, Gagne and his co-author Dr. Kimberly Saudino, a professor of psychological and brain sciences at Boston University, examined 300 pairs of twins. They measured their inhibitory control through interviews with their parents and also by testing and videotaping their responses to temperament assessments in a laboratory setting.
The tests were repeated at age 2 and age 3, both times within a month of their birthdays.
While parent interviews suggested that genetics remains a key factor in these behaviors at age 3, a detailed analysis of the videotaped laboratory behavioral assessments showed that genetic influences were significant at age 2, but not at age 3, according to the study’s findings.
“By age 3, we see that one twin’s exposure to either shared family influences or unique environmental influences, such as more or less negativity from parents, or an accident or illness the co-twin did not experience, are both important influences over their capacity for self-regulation,” Gagne said.
“With a sensitive laboratory-based protocol for measuring inhibitory control, we could map out the traits in early childhood that would suggest susceptibility for certain disorders and potentially help these children faster,” he added.
The research builds on several previous joint twin studies by Gagne and his colleagues on inhibitory control and anger management in children from ages 1 to 3.
“We plan to continue this work following the children as they grow older,” Gagne said. “We also need to study the effects of the situation of parents — their depression, divorces, or other social environmental problems, and how that might affect the development of behavioral control in their children.”
The study was published in the Developmental Psychology.
Photo Credit: Jeffrey Gagne