Spanking Lowers IQ, According to Study
Straus found that children whose parents refrained from spanking scored an average of two to five points higher on IQ tests, depending on their age.
"Spanking has a lot of negative effects," Straus, the co-director of the Family Research Laboratory, told ParentDish.
Children who are spanked throughout childhood show signs of chronic stress, which likely impedes their brain development, he said. Spanking also erodes the parent-child bond, which may impact parents' ability to teach their children new things.
Straus believes that families who don't spank boost their children's intelligence by having more conversations about behavior and expectations.
"If you don't spank, you have to do more explaining," he said. "Explaining to a child improves brain development."
Researchers tested the cognitive abilities of children aged 2 to 4 and 5 to 9 at the start of the study and then four years later. In the 2-to-4 age range, children who were not spanked over the four years scored an average of five points higher on intelligence tests. In the older age group, the children who were not spanked scored an additional two-and-a-half points on the tests, said Straus, who worked with Mallie J. Paschall on the research.
The study also shows the importance of not spanking kids between the ages of 2 to 6, Straus said, because
those children are undergoing "rapid brain development."